Check out autogeek.net auto detailing site. I'm using blackfire paint sealant. So far seems like a great product.
While I really like BlackFire, my first choice would be Optimum Opti-Coat 2.0
Optimum Opti-Coat 2.0 provides a very hard coating that protects the paint, making it more resistant to scratches, swirls, etc. It also is resistant to dirt, debris, overspray, sap, bugs, which makes washing it very easy. If you do not look forward to a regiment of cleaning, this would fit your needs better.
The product is easy to apply and if you follow the instructions you won't have any issues. Below are the basic steps, but you can also find a local detailer to do all this for you.
3. Paint Correct
4. Clean corrected surface
5. Apply Optimum Opti-Coat 2.0 one panel at a time.
Many folks will wipe the cleaned vehicle down with a mineral spirit, just prior to the opti-coat, in order to completely prep the paint and maximize adhering. It is at least a 4hr job, most likely closer to at least 6 hours. So the cost would be a minimum of around $200 for this service, many charging closer to $300.
I will have to get some photos of my opti-coated camry.