Gloves of fearsome grip definitely do stack with belt of giant strength. It's just like stacking the belt with the enhancement on weapons... both affect the end damage, but because they are different things getting enhanced, they stack.
Also, bracers of armor less than 5 are completely useless to anyone in a party with a wizard or sorcerer. Just have the caster cast mage armor on you. It's free, it lasts most of the day... why spend money on something so easily duplicated?
Monk's belt is cooler, if not strictly better, than a belt of giant strength.
I don't know if I'd get a ton of little stuff.. try to get one item as expensive as your DM would allow, and then use the rest of useful things.
I kinda like the skill enhancing items, they're fairly cheap (2500) at +5, and +5 is a big boost.
-The Souljourner