Hi
On esc's - go for a "budget" combo that has an esc and a motor - see this thread
http://www.oople.com/forums/showthread.php?t=69737 for example plus others in teh electrics section. All modern bushless combos work with lipos.
If you go to any of the clubs mentioned and have a chat you can get loads of info - I will be at Roundabout this week and RossMods next. Also, the guys at the RossMod shop, Dave at Roundabout Models in Ashton or Radio Racers in Leyland (plus others!) will help you out.
Personally, I went for a B44 as its strong, simple and spares are widespread, a cheap ezrun 9T 35a combo (will upgrade when I am ready to do so from an ability point of view) from HK and a Spektrum radio set up.