I've been auto detailing for over 30 years and one of the best ways that I have found to remove bugs from the front bumpers and windshield is VERY HOT water in a bucket with some carwash soap and a soft sponge. Use gloves of course! This tecnique seems to melt the bugs away even if you have to use just a little elbow grease. BretF, PW01 and Corvette have some good suggestions as well! For the really tough sticky/gooy bugs, I like the WD-40/GooGone trick.
For tar, I like gasoline even at $3.00 a gallon. It's cheaper the 3-4 dollars for a small bottle of a name brand product. And gasoline won't hurt the paint as long as your going to wash the vehicle. As the matter of fact, I've never seen gas hurt the paint even when left on the paint after a long period of time when filling the tank and getting splash back.
These two tips are part of my very effective ways that I have reduced cost when running my own business and have achieved great results......Trust Me!
If anyone is interested in hearing more tips, I will be happy to share some(but not all) with those of you here on this board.