Megan, T-Max 3200 @ 3200 has good/lots of grain. Also Fuji Neopan 1600 @ 1600 & as Patric mentioned, especially if developed in Rodinal.(posted 8665 days ago)Kodak Infrared is also very grainy.
Ilford 3200 is probably also grain, as is the Ilford infrared film.
Kodak used to have a highspeed surveillance film that was also very grain, but I don't think they make it any more.
chris