Beatport

Beatport is good, yes, can get a bit expensive though. If you are also interested in sets, check out bestdjsets dot net or use something like iRecordMusic or Audio Hijack to download tracks and sets from SoundCloud for free - saved as AIFF the sound quality is surprisingly good. If you want to mix your own tracks or just have them auto mixed, djay for Mac is a simple yet beautiful piece of software for little money, unlike Logic or Traktor. It depends on how deep you want to get into the mixing/producing side of course. 

tp

Absolutely agree with Totemphile, in my experience Beatport is my last resort due to cost - for example last night I purchased The Modern Heat EP by MAM and Trainmann (Tensnake Remixes) by Lauer, both WAV versions. Cost on Beatport £15.04, cost on Bleep £6.48. Considering the small amounts, that's a big difference. No arguing that Beatport probably has the widest selection in that field, and also gets some releases a couple of weeks before the competition. Beatport also have occasional 25% off codes, but be aware that they only appear to cover the core track fee, not the £1 per track WAV premium.

Alternatives I've used are Bleep, Juno Download, Traxsource, DJDownload. I think Traxsource may be US based so you might get charged with an overseas transaction fee by your bank.

Thanks both TP and Nick.I live in US so Traxsource looks interesting as do the others!

Before I was buying whole CDs to get a few tracks, so while the per cost per is not great, the cost per track used is actually quite good.Found a great drum and bass version of Donna Summer's State of Independence.