Moving to Paris
The reason I moved to Paris was because my girlfriend was offered a job there, and we just went. We thought we were fairly prepared for it, she spoke fluent french, we didn't need work permits, and the removal people were happy to look after all our stuff until we found somewhere to live.
Once we had arrived though, we realised that there were plenty of things we hadn't got a clue about. That isn't to say we were all adrift and way out of our depth, but there were quite a few things that we hadn't really done our homework on.
The first was deciding where to live. We had no idea which was the bad end of town, and which areas where out of our league. Her job was at La Defense, and it seemed a sensible start to find an apartment locally - we had already wandered around the area and not got mugged, so it seemed a reasonable thing to do. We could always move later.
Here were the first signs that we didn't know what we were doing. Firstly, La Defense isn't in Paris - it would take another six months before realising we were banlieu, subspecies to the Parisiens. Secondly, at each apartment we looked at, the landlord or agent would ask for our dossier. We'd look back blankly, wondering how important a dossier could be. Again, it would be a long time before we realised that renting an apartment was impossible without a good dossier, or over-crammed folder full of bank details, references and various irrelevant documents (I've known one landlord to demand from an american friend photocopied proof of not just theirs, and their parents addresses, but also their grandparents!). Somehow we hit a lucky break, and met a landlord who rented us the apartment purely on trust. Apparently a near impossible find we now know.
The next difficulties was the dreaded residence permit (the carte du sejour). There are countless pages out there on the internet describing endless back and forth trudging to get multiple forms and documents, copied and translated in triplicate, misinformation and rules made up as they go along. By this time we fortunately had an internet connection, and was able to get some information, but a lot of it contradicted itself, and the only tactic was to take every document you've ever kept in your entire life, from birth certificate to under 12's bronze swimming award. Each time we returned to the prefecture to hand in more documents, it was a desperate trip to Nanterre (remember we were banlieu, so no Parisien prefecture for us). No matter what the weather was at home, it always rains in Nanterre!
Why am I talking about all this? Mainly so I can recommend this book; Living & Working in Paris. I found it in WH Smiths on rue du Rivoli a few years ago, and it was perfect (so perfect that I lent it to someone and never got it back!). Unfortunately the author hasn't updated it since 2001, but it probably is still fairly relevant (he does have a new book called Going to Live in France, but I've not read it).
The book covers the arrondissement of Paris, with a guide to property and rental prices. We would have known about the magic dossier, and would also have been prepared for the exaperating rudeness of estate agents (I'm still waiting for a few calls to be returned).
Emplyoment issues are explained, with CDI, CDD, period d'essai all covered (that's full time, part time contract, and probation period to all us non-frenchies). Tax is dealt is fairly understandable terms, although it usually boiled down to 'pay lots'.
The residence permit is covered, although I've heard it's going to be dropped soon (I'll believe it when I see it! At the very least it'll be replaced with something even more hideous).
And finally, there's a wealth of knowledge on french etiquette (very important, since they invented the word. Although they also invented the words bureaucracy and surrender!). My favourite was something we had already discovered by ourselves, and that if you're invited to a meal with some french people, take flowers not wine. To take wine will insult the host by saying that they have no taste in wine (while having no taste in flowers only insults the wife's taste in flowers, which is not a problem).