Pac-Audio has steering wheel control modules for almost every brand of stereo you can buy, as well as a module with an IR emitter for any stereo that has a remote control like wolfy explained above. Their modules only have programming for up to 5 buttons though. I currently have the SWI-ECL2 installed in my Aztek for my aftermarket stereo and it works great. Only problem is only having 5 buttons. On the site, the SWI-X is the universal module with the IR emitter. Here's a link to the pac-audio modules: http://www.pac-audio.com/Products.aspx?CategoryId=29

Not sure about the Scosche modules, but they seem to all have pictures with an IR emitter, suggesting this is how they all work. Here's a link to the Scosche modules: http://www.scosche.com/car-audio/steering-wheel-controls

I just found this one today from axxess. Looks like it uses the 3.5mm connector that is becoming the norm. Not 100% sure if this would be installable (?) on stereos without the 3.5mm input. But it does have 18 programmable buttons. Here's the link: http://retailer.installationexcellence.com/productfeatures.aspx?retailerid=1273&productid=23230&sid=1D7FEBCC-F2BD-421F-894A-1C6760FE26B8


As for the stereo harness with chime module, here is the one Scosche has and the one I have installed in mine right now: http://www.scosche.com/car-audio/product/538
They sell for a lot cheaper on ebay at times. It is completely plug and play into the vehicle harness, even providing Bose speaker plugs for stereos that also have them. It also provides a +12V accessory wire. Only issue I have with it so far is there is a faint "crackling" noise in the background whenever the little LED within the chime module flash on and off (which is like 5 times a second). It is very faint, but noticeable. Not sure if it is just my unit or an issue with this item. All in all though, a good product. It outputs the chime sound through a little speaker on its own chime module, doesn't sound "boxy" at all though, sounds like it should as a warning chime.

Reviving this thread! I have a Crux chime adapter from crutchfield (discounted to $30 if I remember correctly) since I bought my radio from them. It included the wiring harness and I've had a good experience with it so far.

I got the Pioneer FHX-700BT, and yes the Crux chime box is the only thing you need in order to retain the chimes. You'll need another adapter in order to retain steering wheel controls.