Our first visit in 1986, we booked a package deal through a TA and it worked out really great. Then for our next several visits, I started booking everything myself with very good success. Then in '98 we joined DVC at BWV. Now its just so easy to call MS and get our room, call AA and book the plane, and call Tiffany for pickup. Then with the PS Calulator find out when to call and make all of our ADR's. Now with DVC annual passes, we can now go on a moments notice.
I feel if your going for the very first time, a package deal is really a good way to go. Strange place, not knowing what to expect things are like can be a scarry thing, espically for the amount of money your spending. Once you've gone one time though, there's no reason why you can't start piecing your Disney trip together yourself. Get the books, Disboard, do the research and save money.