I have a variety of kit, a lot of it I can double up from cycling.
A large proportion is from Sports direct, much as i do not like to 'support' them, they do sell cheap items, that seem to be reasonable quality.
If you spend over £60 online, you get free delivery, and the advantage over buying instore is that often it is cheaper online, and they cannot/will not price match in the shops (My local one at least), and also if you send the items back, you get a refund, as opposed to instore where it is only a credit to a voucher card thing.
I have on occasion tried on items in store, and then ordered them online.
MandM direct also quite often have some excellent deals, both on shoes, and on running kit, and there are often some discount codes knowking about, and if you spend over X amount, I forget, £50 or £60 probably, you get free postage - if you pay £1.49, you get a Collect+ returns label, so last time I ordered, I ordered two in small, and two in medium of everything, and then just whacked the incorrect sizes back to them for a refund.
I would also have a look at Royles.biz, have bagged a few bargains off of there, along with Achilles heel.
Also - I picked up a few items from Lidl (I don't have an Aldi nearby) and Amazon someitmes have some semi decent deals, although if it's a third party seller, you quite often will get stung on the postage.
Edited: 10/04/2012 at 14:44