I have to apologise if there are similar threads, I did search.

I have just returned to playing after some time of not touching the guitar, and I am very happy to have got back to the level I was at, and actually a new practice routine has pushed me beyond what I was able to do before technically.

One problem: I can after a time pick up the chords to a song just by listening to it, generally I use a lot of trial and error and finding the chords in that key. But for lead I just seem to have no ear at all. And it is almost embarrassing! And annoying, I will get a good idea for a solo in my head and after 4 hours of trying the idea is lost!

Are there any good resources out there for ear training, or perhaps techniques people can recommend?
start with really simple tunes (like children's songs or well known pop songs) and work it up from there. It takes time, and for most people it can be pretty difficult at first.
will someone carry me across ten thousand miles under the silence
Yeah. I would say start just trying to do songs like christmas carols, movie themes, and nursery rhymes. It'll be tough at first.

I got a tremendous amount of the function ear trainer, a free download from miles.be. Huge help to me. Highly recommended.

A book like "Ear Training for the Contemporary Musician" (by Wyatt et al) is basically a series of structured exercises that get progressively more complex, and can be a good way to build on those other things.