Adding songs to an album from another source

I already had some songs from a certain album in my itunes that I bought from the itunes store, then a friend gave me a mixed CD with some other songs from the album on it. I then downloaded the CD onto my computer into itunes and am now trying to add the songs to complete the album that I already have some of. My computer did not automatically recognize the songs, as they were on a homemade tape, out of order and with some songs from other albums. I have figured out how to add song name, the album and the artist, which makes them show up under the album. I then managed to put them in the right order (using the "get info" control). But the problem is, my computer still doesn't just count them as part of the album and realize that they are the rest of the album, for instance, the rest of the info of the album, the year, extra information, and cover artwork, don't sink onto it still, and when I click the "show complete album" option, it shows all of the songs that I have put in from the other CD as ones that I don't have. So my question is: is there any way to get it to realize that these are the songs in the album and therefore get it to sink the info (cover, extra artist info, etc.) and be considered already owned by the itunes store?