Unfortunately this amp is just over your budget at £300
http://www.avforums.com/forums/showthread.php?t=369607, but you should be able to find the earlier Denon 3802 for closer to £200 now. I own one and can highly recommend it. It has more features than you'll know what to do with. The only real advances in this range of amps is the video switching capability, and upscaling, but I doubt you'll use that very much.
Anything by Denon, Marantz, Yamaha, Sony or Pioneer should do you nicely. There really isn't anything fixed that you should be looking at. Something at £200 from whatever manufacturer second hand should do you fine, just take a look at specs (ignore watt ratings), and see what you can rustle up. Post on here if you need any advice in particular.
http://www.avforums.com/forums/showthread.php?t=369150 Here is a Sony 930 receiver. Very good for the cash, if a little old. The 925, 940, 1070 and 1080 would be worth looking at. The 1080 especially. Old does not necessarily mean bad. The amplification won't have changed all that much over the years, just the addition of different DSPs, 7 channel support and video upscaling.
As far as speakers go, again there isn't a fixed thing to look at. It really depends on what sort of music you listen to, what sort of manufacturer you prefer, and what you can get for the cash. It's ALWAYS worth going to a hi-fi dealers and having a listen there, even if you don't buy. They often have second hand or ex-display things there too.
Manufacturers to look out for: Mission, KEF, Mourdant Short, Wharfedale and Tannoy. Older speakers again aren't bad at all, although you have to be a bit more careful as foam surrounds can rot quite easily. This is only a problem on speakers from the 70's but be careful all the same. There isn't too much to worry about, you can't overclock speakers, or run them differently to how they were intended, and people in general look after them. It is very obvious if a speaker is broken.
There are hundreds of ads on ebay for mission speakers atm. The picks of the bunch are the 753's. Argued by many as the best speakers Mission have made in a decade. In some ways I'm a bit annoyed that I went for their newer 78 series speakers over the 753. There are the newer, but cheaper mission m71, m73 and m74 speakers, which might suit you a bit more, as the 753 speakers on the bay have already attracted quite a few bids even though there are a couple of days left. I used to own some mission m72s which had mixed reviews, but were perfect for my needs, and produced a rather enjoyable "party" sound.
Any of the older KEF Q speakers are a nice option too. Again, it's hard for me to recommend a particular one without having heard any KEF speakers myself, however there have been lots of favourable reviews. Have a look at reviews on the internet.
I hope that's given you a couple of ideas anyway. You really will not look back after hearing a good hi-fi setup.
