Is the bumper damaged beyond repair? Most bumpers, even if torn, can still be repaired. Repair and repainting takes time and a lot of patience. A deformed bumper can be heated to get it back in original shape (may need a bit of a push). If it is scratched all the way to the plastic, an adhesion promoter is required before priming. There are numerous bumper repair/repainting postings in YouTube. Avoid the 'cheapo' solutions.
You can also buy bumper cover online (sample link below) and they come primed already. A matching spray paint kit is available from company like "paintscratch.com." Tri-coat is more expensive. You need an enclosed area like a garage for spray painting. Follow directions on the spray can. Practice before doing the actual job.
http://www.autopartswarehouse.com/searc ... r+Cover%29