What kind of colours are you thinking about using? If you wan't to base them off the GW ones, have a look on the GW website they have made a painting article for saurus.
I won't go into overly descriptive details again now since I'm at uni, but here are a few keywords to search google for. You will find mountains of articles. Drybrushing (very fast and easy), inking or washing (also fast and easy and almost essential for most models), highlighting (more advanced technique, requires a steady hand but build up to it).
Probably the three most important tips I can give you for painting are 1) Water your paints down. Straight from the pot it is too thick, 2-3 thin layers will look better than one thick layer. 2) Don't be afraid to 'mess up a model'. It is dead easy to strip the paint back and start again or just go over any mistakes, you cannot ruin a model. For the same reasoning, push your painting skills! Try new techniques, this is how to improve. 3) Practice! It is definitely a case of the more models you paint, the better they will look especially if you are trying new techniques all the time.
Good luck with it, and feel free to post some pics so we can give more specific suggestions about how to improve.