Readily available on the high street - M&S own brand is cruelty free and contains lots of reasonably priced lines, and I believe they only carry cruelty free external brands.
Waitrose were recently awarded the Leaping Bunny for their own brand products - am using a lovely shampoo/conditioner from there at the moment.
Superdrug own brand products are Leaping Bunny certified (have saved a fortune over last few years since swapping many of my 'branded' toiletries for superdrug dupes!). And they stock GOSH which has become my 'go-to' brand for foundation and mascara since going cruelty free - without a doubt I found make-up the hardest transition (former die-hard MaxFactor devotee here!). I have had success with many of the Barry M nail polishes, although find the finish can be hit and miss depending on the colour.
Holland and Barrett stock lots of cruelty free toiletry lines.
You can even pick up cruelty free goodies with the weekly shop - Sainsburys own brand personal care products are certified.
Interesting info here about how big brands get around admitting to testing: www.uncaged.co.uk/animaltesting.htm
This part especially stuck with me "If you look at a product that makes no mention of animal testing - be suspicious. If a company can make a claim, no matter how meaningless, they usually will." Very true!
Since opening my eyes and researching a little my mind absolutely boggles that now, in 2015, these testing practices continue and are largely accepted as the 'norm'.
Good luck on your cruelty free mission OP