I think the first solo I ever learnt was happy birthday on the high E string!!! LOL!
Seriously now...I think the first 'extensive'
solo I sat down and set myself to learning was Randy Rhodes' "Revelation (Mother Earth)". I had been playing for about three or four years and really loved this solo. I practised it everyday for like 2 months and it never came together, so I just gave up... I'm like that, I've never really learnt a solo at one pop but this was the first I really worked towards getting right.
About half a year later, I was jamming with my mates when I started playing it and it just flowed dude...straight out of me. I was stoked!