Any recommendations for group or private tulip tours for April 2016. Also, given choices is teh canal district teh best area for 1st timers????

Um, Amsterdam is full of canals. Anywhere in the center will be near canals.
And yes, you do want to be close to the center to be able to walk to as many places as possible.

I encourage you to look at a map, locate the places you want to see and hte locations of hotels you are considering.

And goamsterdam.about.com/od/daytripsexcursions/tp/guidetotuliptimekeukenhof.htm gives you some information on seeing the tulip fields. Flowers being flowers they have the nasty habit looking at the weather rather than the calender. There is no guarantee the tulip fields will be in flower when you are around.

easy enough to do on your own - take a train to Leiden bus to Keuikenjhof then bus #100 thru the heart of the flower/tulip fields to Haarlem - get on and off where you want to tiptoe thru the tulips.

http://www.keukenhof.nl/en/

The Keukenhof Gardens are the prime place to pinpoint to see flowers as their best - not just tulips but loads of other blooms too - includes hothouses housing the best of the Dutch flower industry products - many of which are shipped to all parts of the world from nearby Schipol Airport.