There are a number of options available for awnings for small campers in the US. I've broken them into a few classes of awning below.
These awnings roll back into a protective case, using either a hand crank or an electric motor. They can be rolled out to any percentage of open, meaning you can pull out just a small bit if space is limited.
Fiamma F45i ($700 + brackets + freight): this is the premium campervan awning. Aluminum case; hand crank with optional electric motor; heavy-duty material. It comes in 8' and 10' lengths, and pulls out to over 8'. It's heavy, at 49 pounds, and care should be taken when mounting it. There are no factory brackets for Ford vans; Sportsmobile offers this awning on its vans, but some have reported cracking of the van sheet metal around the bracket attachments. Others have had success modifying some of the VW brackets, or creating their own brackets. Where to buy: your local RV store can order it from Fiamma, or visit gowesty.com. Expect to pay $100 to $200 freight from Florida, even when purchasing from a dealer. Group buys can sometimes be found on your local craigslist - I've seen them recently on the Seattle board.
Fiamma F65: larger than the F45, otherwise similar. All Fiamma awnings should be ordered from your local RV store. You'll pay Fiamma's listed price on their website, plus freight. For an F45, this was about $175 to WA state - expect to pay about the same for the F65.
Dometic Horizon (aka A&E Horizon) (~$800 + freight): Now known as Dometic, used to be A&E. Either way, it's made by Fiamma! It's the same mechanicals as the F45i, but different fabric. An older version of this was known as the Transawn 2000.
Rhino Rack Foxwing Awning ($600): Very cool - comes out and wraps around 270 degrees, to shade the side and the back of your vehicle. 100% UV protection, and available for either the left or right side of the vehicle.
Fiamma F35 Pro: another nice awning from Fiamma. This one's not a crank-out awning - you pull it out to full length, attach the poles, and you're done. Takes a bit longer, generally requires 2 people, but is smaller and lighter (and cheaper!) than the F45i. Contact your local RV dealer to order one, and expect to pay over $100 for freight.
Hannibal: Hannibal is based in South Africa, with no dealers elsewhere that I know of. The awning is an interesting design, and uses fold-out supports that I think need to be mounted to a Hannibal roof rack. The supports are strong enough to hold up the awning without any poles or guy ropes. Price unknown.
More pictures and information on this ih8mud.com thread.
Mombasa: I've seen the 6.5' awning for sale for $260 shipped (from trdparts4u.com). Check the ih8mud forum for occasional deals. See ARB and Campinglab - these awnings are all the same, from the same factory. A nice looking, lightweight, well-made awning.
(picture from http://rides.webshots.com/photo/2654877880034696539FqKKsK)
ARB Touring Awning ($250): As mentioned above, this awning is the same as the Mombasa and the Campinglab. All good awnings, with 100% UV protection. Intended for mounting to a roof rack, but brackets are available for some vehicles, and the awning's relatively light weight makes it easier to mount than other, heavier options (such as the 'box' or retractable awnings).
Campinglab ($250): the same as the ARB and Mombasa awnings (to the point of being made in the same factory!). Available in two sizes: 79" ($250) and 70" ($225). The web site doesn't mention a spring-loaded roller, but the Campinglab rep on Expedition Portal mentioned a redesign which includes this feature, for easier take-down.
Shady Boy (~$450): a pole supported awning that goes together like a tent, with poles and sleeves to be assembled. It has a nice aluminum case that attaches to the side of your vehicle, and weighs very little when compared to the larger, fancier awnings (about 15 pounds / 7kg). The Shady Boy folds out from the case to the front and back, ending up with a length 3x that of the case. These are popular with the VW crowd.
(photo from shadyboy.com)
Bus Depot Ezy-Awning ($120 plus mounting accessories): a simple pole-supported awning that goes together like a tent. Lightweight, inexpensive, and small to pack.
Kelty Carport Deluxe (~$260 for the large): kind of a half-tent, meant to be installed next to your car as an awning or shelter. Requires a good deal of setup, but provides good shade and protection once it's up. There's a good review of it at lastgreatroadtrip.com, and it currently gets 4.5 stars (out of 2 reviews) on Amazon.