There are a really good number of entry level calls out there that can sound good. I will suggest the Rich-N-Tone Hunter Combo. A very attractive Cocobolo wood call and an instructional CD are included in the package. A double reed call will be easier to work immediately, but in the long run I believe a single reed is the superior call. A single allows you more finesse in your presentation.
There are other very good makers out there so find a call that you find appealing, add an instructional tape/cd and practice as much as your able to. When you figure your sounding pretty good, get another instuctional tape and gleen from it what you can, and then another. Every one I have bought has given me some little thing to use. Then next spring, goto the park and call at real ducks in a pond. They will get you practicing even more. There is no such thing as too much practice. The best callers in the world still practice daily and even a tin eared journeyman caller like me carries calls year round in the truck and really starts working them hard around april in preperation for the season opener.
Hope this helps a little. Again, there are a lot of good calls out there. Your first call may be chosen on looks alone but get one from a good name maker and practice, practice, practice.
"If you don't think too good ... Don't think too much." Ted Williams