you spelled grout as "gout" in your title, probably not what you want to be working on
as for stone work here's a quick run down. if you have at least a portable that can create 800-1000psi you can run a spinner. if you don't tile and grout can be hand cleaned with great results provided you understand the chemistry and get use to quality products. all of my tile crap has came from either jon-don or lowes. lowes sells dupont and at a good price. you'll find two main styles of grout, actually 3 but 2 are similar, anyway they are
sanded and unsanded should be resealed after cleaning. actually it's not a bad idea to do all 3 but it's mandatory with the first two since you actually remove a small amount of material when you clean them
for tile cleaning you'll use different chemicals and different tiles and different levels of grime. acid for example works like a charm to remove hazey sealer from slate and get the white clouds out of the stone. if you spend some time on google, youtube and asking around or taking a cert class you'll learn quite a bit
a good cheap sealer for sanded and unsanded is 511 from the home depot, it's solvent based, not water and a good product that's easy to apply.
mentioning of sealers there are some granites you just can not seal. absolute black is one that comes to mind. it's just too dense and the sealer will streak on top.
i could keep rambling but there's a start for you
also, google bud cline
that guy is like the tile god and reading the posts all over the various forums he's made will teach you a lot