If you go with the Toto, you will need to buy a seat (or reuse the seat off your old toilet if you liked it and it fits the size of bowl you will be purchasing). Toto has standard seat-bolt positions, so you can use any brand seat. It won't fit the bowl exactly, necessarily, and the Toto seats are nice, but some people (including us) simply reused the Mayfair/Bemis seats we liked. There are two basic sizes of bowl, elongated or round, and the consensus here is always go for elongated unless you have a fixed space issue like a door swinging into the toilet, which you don't.
You will not need to buy tank-to-bowl bolts because the Toto ones are fine. I would double-check about the closet bolts (used to attach the toilet to the flance); they are said not to come with the toilet but I have this weird recollection of having some in the bag with the bolt caps (which ARE included), although maybe the bolts came in the box with the fancier wax ring I bought. You also need a wax ring.
SO: Hardware you need is: (a) a good brass closet bolt set [Terry uses Pasco brass closet bolts model #28, which has two bolts and 4 washers and nuts], about $1.50 at a good hardware or plumbing supply store; and (b) a good wax ring, no flange or sleeve needed according to most posters here [figure $2-ish]. And of course you need a seat.
I have seen Terry suggest that one always replace the flexible water supply hose at the wall when replacing a toilet, but you have a brand-new one from your plumber, so you don't need that.
(edited to fix horrendous typing job I did on my phone).