A comprehensive database of lenses which will work with your camera is available at Dyxum along with user reviews.

Kurt Munger has a lot of reviews on his site as well.

Second hand you should be able to pick up a Minolta 50mm F1.7 AF or 28mm F2.8 AF quite cheaply.
Sony's 50mm F1.8 SAM and 30mm F2.8 SAM Macro are both good optically and quite cheap new if you don't mind the all plastic build.

For telephoto it depends how much reach you need, the cheaper 70-300mm lenses from Tamron/Sigma/Sony/Minolta are all fairly similar in quality, Sigma's 70-300mm APO DG Macro probably the best (though it has a reputation for stripping it's focus gears on Sony cameras).

Where is a good place to get a lens, and what is 'cheap' considering it's all subjective, seeing a lens for £150 seems like a lot to me but I don't see the scale of value having just started

Fin, check out the links section of this board - there's a few good sites listed, including http://www.camerapricebuster.co.uk/

warehouseexpress.com are normally fairly competitively priced, or for stores you can walk into I like Jacobs. As for prices I don't know anything about Sony lenses so I daren't comment.

Doesn't answer the bit about pricing but thanks

Also is buying used ok? I was thinking of starting out with lenses this way as a cheaper means and a lot of people are saying to get the old Minolta AF lenses but don't know what kind of price I would be looking at or what to look out for with damage etc

Did you check out my link? It'll give you a run down of the available Sony lenses and who's stocking them cheapest. If that doesn't give you an idea of market prices for Sony lenses, I'm not sure how else I can help.

The Minolta AF lenses hold their value very well, because of the DSLR compatibility (which is why I've never got round to buying a lens for my X7000 body).
You'll need to look out for fungus/dust on the optics and sticky aperture blades mostly. Neither of which is terminal, and I can point you in the direction of a company who'll service Minolta lenses for about £25-30.

I did but it was only the official lenses etc, nothing about approx used prices etc

The trouble with used lens prices is that they will depend on a lot of factors, good examples of the more sought after lenses can sell for more that their original price.

If you consider the 50mm F1.7AF I mentioned in an earlier post there is one on ebay at the moment for just over £20 pounds. My local Camera shop had one on sale for £79 a few months ago.

Even if you need to use the Minolta service (mentioned by the Prof) at £30 the ebay lens is still cheaper but you can't check the lens quality before buying.
Personally I'd prefer to buy a used lens from a local shop as I can at least test it prior to purchase and most will give a short guarantee, but if the 50mm on ebay is good quality then it's a bargain if it sells for under £50.

As to what is cheap, well I would say any new lens at around £150 or under is cheap, though at this price there are usually some compromises with either build or optical quality with new lenses.

The kit lens which comes with the A450 is one of the better ones according to dpreview so unless you want/need something faster within the 18-55mm focal range then I'd spend available funds on something with a longer focal length first.

I'm betting that'll go north of £50 before the end of the auction.

Plan was to get a zoom lens first and possibly a macro lens later to have a reasonable set of covering most bases

Is there much point in getting a 50mm lens with a lower f value (lets more light in so can shoot at a higher iso?) early on or is it a case or using it with manual focus to get better at taking pics? Been relying on the AF and the presets currently which is ok but I'd like to be able to compose better shots and I think a manual focus is useful for that (?)

I think a 50mm lens is the most rewarding in some ways. A low f value means the lens is faster so instead of having to select a high ISO like 800 on a lens with an f/4, with that 50mm f/1.7, you could get away with maybe an ISO of 200, which generally means a less noisy picture. Or, you can get set up on ISO 800 and a wide open aperture of 1.7 and get some really high speed shots.
The flip side of this is that the smaller your aperture, the less depth of field you get to play with (the amount of image in focus).

Whatever, a 50mm is a lovely lens and everyone should have one. It's the one I'll fall back on most often.

So in that case, in order of versatility:

zoom (beercan?)
50mm
macro

Would that be a sensible way to add to my kit lens?

Just to muddy the waters, you can get get combinations such as the Sony AF 50mm f2.8 macro. However this comes at a higher cost and a 50mm macro could mean you are right on top of your subject.

There is no "sensible way" to add to your lenses, because it all depends on what you shoot and how you shoot it. Yes, people can say the best lens they have is such-and-such, but that's them.
Your requirements are going to be different.
We can all tell you what we think would be best for you, but that won't really help you until you know what you want to shoot.
If you want to add to your lenses then that's fine, but I don't see how you can outline a list of lenses until you know what you want to use them for.
Don't just say to yourself "Plan was to get a zoom lens first and possibly a macro lens later to have a reasonable set of covering most bases", work out what you think you need them for first.

Mark

Fin, I started with a twin kit lens (18-55 and 50-200) and they were good enough to get me started cheaply.

When I returned my original camera for a refund (fault) I could only get the single lens kit (18-55) so I bought a cheap 70-300mm. I find the focal length really useful and for what you pay its a resonable lens but I try to use it upto 250mm only as it gets a bit soft.

As I started to use the camera more and more and dream up projects (and read about them in mags) I found my lenses weren't upto the job. I guess I have a list of lenses I want in an ideal world but havent rushed out to buy any. Recently though I especially wanted to start a project photographing my baby and was craving a macro lens too to play with too.

In the end as I had identified a proper need for the lens I picked up a Sigma 50mm f/2.8 macro. Its not as fast as a Canon nifty fifty for example but it works well for portraits and is a proper 1:1 macro. In a perfect world (going back to the wish list) I'd have bought a Tamron 90mm f/2.8 Macro and a fast 50mm but money was tight having had a baby and all. I had to base the decision on what I needed balanced with what would be best value - after all I'm not a pro making money out of this hobby.

I can honestly say though the lens is a cracker and it hasnt been off the camera. I love playing with macro, I take a portait of my baby everyday and it has barely been off the front of the camera.

I guess what I'm really saying is use what you get to start with and then make an informed decision on what extra you need as you identify that need. I would imagine most people have a wish list of lenses but honestly if I bought that Sigma 10-20mm I'm after I really wouldnt get the use out of it I ought to. On the otherhand a 28-75mm faster kit replacement is now my absolute next buy and will make a more sensible and useful purchase.

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