Do you have them on another computer or disk that you can copy onto the newly reinstalled computer? If you are asking if there is a way to pull them off the phone and put them on the phone then you need to get hold of a program such as Tansee iPhone Transfer. It is not free but it allows you to pull music, videos, etc.. off your phone.
The album covers are easy, just hilight all songs, right click and "get album covers" iTunes will get them. Also same with getting your purchased music. Right click and you can get all the music that you have purchased.
ok will wipe my iPhone and start over.. but the song i have are from off the net and the people who send them didn't have the right name and didn't know the album and some where the wrong name and so on. off to working on the songs i go