It does'nt have to be an expensive one, jessops do some fairly solid tripods for about 20 or 30 quid! which are quite adequate for indoor use.
Its just that with macro, you will find yourself wanting more depth of field (big f number) than the lens can provide wide open(possibly f2.
, hence slower shutter, hence tripod to avoid camera shake.
Also a good tip is that if your tripod is on floorboards dont walk around while your doing a long exposure, slight movement will bugger it up
You dont need a tripod for bee shots, you hav'nt time, so get yourself out while its still nice and bring us something back to look at