First tries, using the Canon 50D and Canon 5D mark II together with the Speedlite 580EX II.
When I bought the Speedlite, they adviced me to get some colorfilters as well. Those filters, indeed, take away unnaturial colors and give an overal balanced whitebalance.
The other important skill to develop is bouncing. Be aware of the influence colored surfaces have on the toning of your photo!
These photos are all taken using the Canon Speedlite 580 EX II. The first album is done with the Canon 50D, the Wedding with the Canon 5D mark II.