Job-wise, definitely make sure that you have a UK-style CV. If you're unsure how to do that, or even if you just want to run it by someone, most public libraries will have a job club or something similar.
Definitely get some UK experience ASAP. I work at a council-run library and we are always looking for people to do what is called peak relief. Basically, when employees go on holiday, we have a few people who we can call to fill in while they are gone, similar to seasonal work. Someone small like that may just give you the experience needed to break through into the UK job market.
