<font color=lightgreen>
I mean any serious stuff, not ur average spells and +1 weapons.

Anything proper?

I thought ring of woodlands was okay but SR of 16 is still quite useless.

SR doesn't stack right?
(otherwise... CRAP!)

</font>

Thayan circle, Golden circle, battle robe, rign of clear thought, rods, wands, boots of reflexes etc etc etc etc.

There are a bunch of things you will like, the problem is deciding what you need the most.

The trouble is that you can get all of those items out of chests or barrels or off dead baddies. I'm playing a socerer & have never had to buy anything. Sold plenty of stuff though. Sorry, told a lie, I did have to buy bolts for my x-bow.

there are a few "big ticket" items for a wizard to buy, but nothing on the scale of robe of vecana from bg2.

greater swordsman & brawler belts - these are quite possibly the most overpowered items in the game, imo, worth every penny to buy them early.
rings of power.
amulets of health.
boots of speed.
some of the robes are ok. master adventurers or greater battle robe (but neither are that powerful.
bags of holding. for a low strength mage if you are a packrat these are must haves. (i'm kicking myself a bit for not buying some earlier)
potions of heal (really the only potions i keep around, for everything else i tend to use health kits.)
spell scrolls (obviously)
cloaks. i prefer fortification for the ac + saving throw bonuses, and odd i've not found a cloak in game that is much better than the manny starred cloak. but the nymph cloak +5 is good for tooling around town.
the odd weapon here or there to improve / forge.
greater helm of persuasion very usefull item, and can make up a lot of ground w/ the high cost of cross classing skill persuasion & allows for low cha scores.

the stores in general seem better for multi classes, my single class chars seem to find all that they need. save an item or two. and it always seems like i have a lot more money than i need.