I've been commuting about 75 miles each way in work clothes. (dockers)
I've been wearing my chaps over them, but it's still cold in the center area. I also still need to wear rain pants, and have 0 protection where there is no leather.

I just bought some Firstgear HT 2.0 overpants. They fit well over my dockers, and don't cause wrinkles. They are waterproof, have full length leg zippers, special heat resistant fabric on the lower legs so they don't melt to your pipes, and a zip-out liner. Oh, and armor in the knees and hips. Not to mention, a whole ton of pockets.

I highly recommend them. I did quite a bit of research and these came out on top. Picked em up for 140 on ebay.

I'll still wear my chaps with jeans, but I'll wear these on my daily work commute and in the rain.

Did I mention that chaps over dockers looks pretty damn funny? Even my wife cracks up, and she never said anything when I wore em with jeans.

 

Just a thought, be sure to read the return policy well. It seems chaps can be hard to fit. You want to be able to return them and go elseware if you want.

 

I bought some chaps recently from chopperleather.com. They were $84 shipped and I have been pleasantly surprised at the quality. They're lined and have heavy duty zippers and hardware.

 

I'm 6'4" and found reasonable chaps in tall at www.bikersden.com. So far I've been real happy with them.

 

Leather up.com. Been riding with them last two months. Pakistan leather, but thick and supple.

 

Check out some of the Army-Navy supply stores they might have what you need or some after market stores, justmake sure you try them on. That way you know what you get.

 

Carhartts are a decent choice...try Gemplers for those. I got a pair of xpert naked leather durango chaps from hempandhawg on ebay clicky clicky. Good fit and they are lined, plus how can you go wrong with a name like that . For the really cold days here in SoCal (LOL) I wear a pair of gore-tex pant liners under the chaps.