Nice and easy mate. Look at the back of the engine where the block meets the gearbox. You will see the starter easily from there. Undo battery so no power going to it. 2x 13mm nuts hold the battery and earth cables on respectively. (normal ring spanner will do) then there is an 8mm nut holding the ignition wire on but check the rest of the wire first as a lot have already been replaced and they have added a spade connector which is easier as if thats the case, just pull the spade connector out. There is then 2x13 mm bolts and (i think this is right as far as i can remember) a torx bolt-unsure what size. These bolts hold the starter onto the bell-housing. the middle one is easy as thats visible so start there but dont take it right out, leave a couple of threads. if you imagine looking straight on at that bolt, the other 2 are at 3 and 9 oclock. once they are off, wiggle and pull. the middle bolt has a dowel so be careful not to lose. Will probably stick in the starter so pull out with long nose pliers if sticky. Fit new one in reverse of removal and bobs your mothers brother. I would recommend starting by putting middle bolt in though but dont tighten right up, you will then need to put your other hand round the other side of the engine (under inlet manifold) and hold/rotate the starter slightly until the bolt closest to front bumper gets a thread.
Hope that helps you chief but if you need anything else gives a shout, i check this page a lot.
:0)
SB, July 2009