Hi, Frome a budgeting point of view, I can reccomend the M-Audio Oxygen 49, it was one of the first controllers I used. Its very good as its a 49 keyboard which includes 8 sliders and 8 knobs to which you can map to your synths lfo knobs...etc.
If you check WWW.FROOGLE.CO.UK and search for it I believe dolphinmusic.co.uk are doing it for around 59 pounds plus vat. Order your froogle results cheapest to highest and you should find it. Good luck!