Federer for footwork/movement. Federer & Nadal for the way they focus on the contact point and keep the head still for (nearly) all of the forward swing on groundstrokes. However, I would not try to copy the straight arm technique on Federer's and Nadal's forehands. This technique is more for advanced players than for most intermediates.
I like Agassi as a model for a compact, classic version of the forehand. Sampras, Safin, Moya and Blake are also worthy of inspection. More modern FHs include Gonzalez, Moya and Murray (even tho' it's not as big as some of the others).
For the 2-handed backhand, take a good look at Nalbandian, Safin, Murray and Djokovic. You might also take a gander at Davydenko and Nadal. For the 1-hander look to Justine Henin, Haas, Federer, Blake and Kuerten. While Gasquet probably has the best single-handed BH of all time, it is not one that should be emulated.
Federer and Sampras for the serve. However, I would probably go with a simpler takeback/preparation than Sampras used on his serve. Consider an abbreviated or hybrid takeback for the serve motion.