There are a lot of great guitar solos to reference. It's funny but you don't hear that many guitar solos in popular songs anymore, it seems to have fallen away from favor.

Here are a few of my favorite solos in songs. I will leave out the ones that have already been mentioned (David Gilmour's solos, etc)

The Cars: Best Friend's Girlfriend
This is a great solo with some very cool rock-a-billy references in it. Elliott Easton always played very tasty solos in the Car's tunes, but this song is my favorite example of his playing. I read in an interview that Elliot Easton was heavily influenced by George Harrison's solos in Beatle tunes. He was referncing the Beatle tune "I Will" in the main guitar riff in Best Friend's Girlfriend.

Journey: Lights
Although I'm not a huge Journey fan, however, this song stands out as one of the best guitar solos in classic rock tune in my opinion. He is giving a tribute to Hendrix in this solo with his tone and overall style. The solo is melodic, uses some great Hendrix-style lines, and it really fits into the song in a nice way. I never get tired of hearing it.

Steely Dan : Realin in the Years
This solo is loaded with cool licks that fit the chord changes perfectly. I always liked the guitar players that Steely Dan used because they all sounded like Blues players who knew how to play over changes like a Jazz player would. I learned a ton by copying licks from guitar solos from Steely Dan records. Check out the guitar solo on the song "Peg" also. This is only one guitar but the way he uses double stops sounds like two guys. The "Peg" solo was done by studio guy named Jay Graydon - incredible player.

Dire Straights: Sultans of Swing
Mark Knopfler is just one of the most original players. He is one of a handful of guys who are identifiable after only playing a few notes. I like his solo in this song because it builds nicely, he nails the changes, and he uses really cool phrases due to his use of fingers instead of a pick.

There are many more, but I stop with these ...

--Jim