What to consider when learning to make sushi at home?
There are a few tools you should have that are out of the ordinary in a typical American kitchen:


Sushi rolling mat - It's really the only way to make maki (rolls). Pro tip: when you use it, put it inside of a large zip-loc bag. This helps prevent the rice sticking to the mat.
Wooden sushi bowl - This is essential in helping the rice turn out properly. The one I linked includes a free mat. I don't own this particular brand; I bought mine from an asian grocery store near me for like $30, it came with a paddle. If you don't want to commit to this large uni-tasker then I recommend using an equally large shallow-ish plastic bowl/dish. The sushi chef that taught me said plastic was OK, but to avoid glass or metal.
Quality rice cooker - A quality rice cooker makes life amazingly easier. I own the one linked and it is amazing. I use it for cooking all of my rice. The quality of Zojirushi is simply unsurpassed and it quickly pays for itself.


The single most important thing is a very sharp knife. It makes cutting the maki SO much easier. I can't stress this enough. A chef's knife is just fine, but it should be well cared for and very sharp.

For beginners nigiri-zushi is by far the easiest to make. You simply shape a small amount of rice in the palm of your hand and slap a piece of fish or other seafood on top of it. Cutting the fish for nigiri is an artform and cannot be adequately conveyed here, but if you just hack out a thin piece of the right size it will taste fine. Tuna and salmon are relatively cheap cuts to use for this.

For maki I suggest starting with spicy tuna rolls and California rolls. All you need for a California roll is: avocado, cucumber, and imitation crab meat. For spicy tuna mix you need: tuna, kewpie mayo, and shichimi togaroshi (or nanami togaroshi). 

You may also want some tobiko and/or masago roe for the outside of your rolls.