Budget? For under £1k I'd say a GTE/GSi Nova or a 205GTi as parts for modding are very cheap and easy to find. All you need to do to either of these is suspension, wheels and tyres and you have a fantastic track day car Nearly bought a 1.6GSi Nova before the civic, and that'd been modded for night-time navigation runs. That was a helluvalotta fun.
You want somthing that we it breaks you can get parks quick and cheap.
Like scooby says RWD is best.
My xr4i is taking its time but thats my trackday toy.
I would go for a E30 320 or 325 loads of parts and you can get a lsd cheap they are light quick and have strong engines and gearboxes and there are plenty on ebay.
Or dare i say it,an escort RST (can still find some cheap and engines are easily brought up to circa 200BHP)parts will be dirt cheap
IF its ur first one maybe try a 2.0 DOHC sierra and strip it, u cud pick one up for under 400 quid tac and tested. thinking of gettin one of them meself to learn drifting basics