What exactly are you after?
IMHO there is no need AT ALL for a solicitor to pitch to publishers - and they would not help you with this anyway
If you are looking for formal copyright protection and legal advice on contracts, agreements, publishing deals etc. then I think your best move would be to join the Guild Of International Songwriters & Composers (GISC):
http://www.songwriters-guild.co.uk/ As a members you will get access to copyright protection, legal advice and a range of other benefits
However, the most important thing you need is commercially viable music
I would suggest hanging around this forum for a while and post some of your music for review by the excellent members here and review some songs