Let me tell you about agencies.
Agencies post things online to try and fish in your resume. Then, if they like you, they will call you and make you come in and learn about you. Some are very good and take what was said at that meeting and DO something with it. Some are RUBBISH. They all promise to be responsive and make you look good.....but i don't believe it.
I had some really good ones. And Some shoddy ones. Funnily enough i got this job from the first one i met, this cocky american guy who i never thought would place me. And he got me the best job! At no cost to me.
Agencies are good. They do both perm and temp placement. I took this job temp to perm...and worried for 2 months they may not hire me (i turned down a perm position for this one for a few reasons...)....but they did.
But yeah, when she gets here she should register with agencies. Make sure they are willing to fight for her. That she should find out which are good in the area and just send on her resume, not for a specific job as they are usually outdated. Let her be confident-don't let them tell her she won't be paid well if she has good credentials. If i could get £5 for every time someone said 'your CV is outstanding.....but since you're american and don't have the UK experience, you can expect to make LESS that others' i'd be rich.
So i took a job at an american arm of an english company and was never discriminated against once. it's great!