You will probably hear a lot of different opinions, but I painted my block with POR-15, gloss black. There are a number of different types of paint to use, it's all up to you. POR-15 have a very good reputation for holding up. As far as the accessories, you can use just about any 500 degree paint on the market. It's not going to hold up like powder coating, but it's not as expensive as powder coating.
They have an engine kit for around $40.00 that comes with everything. Kind of expensive, but you get a lot of stuff in the kit. You might as well do it right the first time. They have quite a few colors to choose from also.