I think it depends on what you want to fly / what you have flown.
I did my PPL (mostly) in a PA28 and had no problems. Once I had it a friend suggested I might like to fly his Auster - when I wanted to go around a corner I would bank it in the appropriate direction and the b*****d thing would just carry on where it was going (but it didn't half feel uncomfortable).
After a couple of (frustrating) hours my mate suggested we drop into a gliding club - he seemed to think that flying a glider would help me understand what the "foot rests" were for.
My first flight was AWESOME. The visibility - sitting in front of the wing in a "bubble". As we went downwind I can remember thinking that "we should turn base now....really NOW....OK we're not going to get back to the airfield", followed by finals "we're never going to get there.....OK, we might.....Oh !!!!, we're going to overshoot the end of the airfield (1000yards away)", then the airbrakes came out - WOW!!!!
Fast forward......past Silver 'C' and around 100 hours in an Open Cirrus
I still find it completely awesome that I can get a winch launch to around 1000', cruise around for 4-6 hours and then land back where I started - WITH NO ENGINE.
Also I have recently got checked out on a Tiger Moth - during which comments like "you can always spot a glider pilot 'cos they know what the rudder is for" made me feel good and meant the upper airwork / PFL / spinning / ... was sorted on under 2 hours. (We'll skip over how long it took me to sort out the landings - not been able to see ahead really threw my height judgement).
I would suggest you do a trial lesson (book it direct with the club - its far cheaper) and then consider doing an intensive day/week course. Take a look at:
http://www.gliding.co.uk/findaclub/ukmap.htm and, once you've considered the others pop into
http://www.shenington-gliding.co.uk and they'll sort you out.
