depends how much $ u wanna spend...volvotuning.com has a fairly extensive list of aftermarket and oem vendors as well as links. check it out (wish i had earlier). different venders sometime have different prices on same things, shop around.

cheap ones would be to put in a set of strut braces ($100-200) that stiffen up your chassis, u'll notice it...believe me. it's also pretty simple to install, shadetree mechanic should be able to do it :). sway bars is on hold, as i know no one else other than ipd make them, and they're reworking it or something. as for springs and shocks, as well as rims and tires, wait till your current ones wear out and save yourself some money, stock springs and shocks typically last 5-10 years, depends on mileage too. yours might be getting there. 16" rims are a decent upgrade, won't jar ur ride like 17", but give a good mix of handling and comfort. and it's cheaper, and has a broader range of tire selection. go for good summer tires, then if you need snow tires, u can put a set on those 15" u have and don't ever have to worry about them anymore, just swap the wheels come winter time. exhaust and ecu are simple upgrades, i did those myself too. most of these things are pretty durable. erebuni has some pretty interesting body kits. i just went for the t5-r front spoiler. u can also rework the brakes...cheapest one is to get some stainless steel braided brake lines, replace the current ones when u get your brake fluid flushed. some have differing opinions as to cross-drilled brake discs or not, it's up to u. think of it this way, it's true cross-drilled/slotted provide enhanced performance, but most of us won't notice it that much unless on the track. plus, there have been cases where the extra holes lead to cracking. then again, cross-drilled and/or slotted discs look cool =). easiest way is to have your current pads wear out and put a better pad (many choices out there). hope that helps