I'm getting more and more emails from people trying to get started in book illustration so, to save writing individual replies, here's some more general advice, this time about getting yourself noticed.
Firstly: spend some time browsing the children's section of bookshops. Familiarise yourself with what different publishers do. Bookshops are better than libraries for this, as it's all still selling, so never out-of-date.
Get a copy of The Children's Writers and Artist's Yearbook (or something similar - there are a few different ones). This has listings of all the publishers with their contact details, as well as more advice and guidance.
Make colour prints of maybe three of your best pieces, marked with your contact details or, if you have the necessaries, design an A4 flyer, like the one here. Post these with a short covering letter to the publishers you have researched.
Unfortunately, publishers get unbelievable quantities of unsolicited material, so you have to work very hard to catch their eye. Here are a few hot tips that worked for me:
1 - Make sure you contact a named Art Director or Commissioning Editor (never send a 'to whom it may concern': it will probably go in the bin).
2 - Ensure any samples you send are produced to high quality - first impressions DO count.
5 - Get on-line: set up a simple website, or a Flickr portfolio, to refer publishers to (but resist the urge to pad it out with your less-good work).
7 - The scatter-gun approach: do all of the above for lots of different (but relevant) publishers.
8 - Don't give up too easily: take on board any feedback you're lucky enough to get, but don't be put off by lack of success - even if you're good, it might take a while for someone to bite.
If in doubt about which individual to contact, don't be afraid to phone the publisher's switchboard to get the relevant Art Director's name. In your covering letter, tell them you would like an appointment to show them the rest of your folio. This is important, even if you're not local: I have always found that face-to-face contact is the thing that works. For me, samples sent out and website links are all about getting publishers to ultimately let me visit them at their offices, to present my work in person.
Don't be too disappointed if the Art Director doesn't remember your samples when you phone - they get hundreds. Ask again if you can make an appointment to visit them with the rest of your work. Be ready with a simple website or Flickr page, so they can quickly check your work on-screen.
OK, now the bad news. Children's illustration is a very tough market to break into: there's so much competition and the standards are very high. My experience is that slogging round publishers and bombarding them with reminders about your work is the only way in.
However, if your illustrations are of a high enough standard, are interesting, clever and relevant (perhaps even a little bit different, without being too off-the-scale), you should eventually get your foot in the door, if you stick at it doggedly enough.
If you are successful in getting an appointment with an Art Director, you might want to read this post, to give you some idea of what to do and what to expect. Or why not read about how I got my first book?