I recently answered some question over on Sarah's blog and thought I'd reproduce my answers here in case they're of any help to anyone else. Hopefully Sarah won't mind me reproducing her questions...
NB: These are my opinions on the matter (based on research I've done and writing forums I've visited). Other people may disagree with my advice!
1. In Writers and Artist Yearbook in the Literary Agents section is says 'No unsolicited MSS' in some of the agents profiles. What does that mean?
It means - no unsoliciated manuscripts i.e. don't just package up your entire novel and send it to them! It may also mean 'don't send your synopsis and first 3 chapters either'. If you REALLY want to place your novel with someone who says no unsolicitated manuscripts you should just write them an email or letter instead. Kind of like a cover letter - telling them what your novel is about, what market it is aimed at, what the title and word count is and some background about your writing history. Oh and a stamped addressed envelope. If they're interested in your novel they'll invite you to sent in the synopsis and first 3 chapters.
2. Can you send to more than 1 agent at at time or is it best to wait for a response first?
Most people tend to send their novel out to between 5-10 agents at a time. As I said in my blog agents can take between 6 weeks and 9 months on average to get back to you so if you only send to one at a time and each one takes 9 months and then rejects you it could take a long, long time to get an agent! As/if the rejections roll in you should send it out to some more agents so your novel is always 'out there'.
3. What is the better route of sending your writing, agent or publisher first?
I'd suggest you send it to an agent first and only approach publishers directly if you can't find an agent. An agent will negociate your deal with the publishers, could potentially set up a bidding war between different publishers and will handle any foreign rights issues/publishers. If you go straight to a publisher you'll have to handle those negociations yourself.
4. What kind of word count is best to aim for when writing? My genre of choice is what is sometimes classed as 'chick lit'. Some people like that term and some don't. I don't mind it.
Chick-lit is around 80,000 - 100,000 words although the more established authors are normally asked to up that to around 120,000 words for their later novels. There's a rumour going around that Marion Keyes new novel will end up over 200,000 words! That's the exception rather than the rule and debut novelists should stick to 80,000 - 100,000 words.
5. is it best to have completed the whole book before sending off synopsis and first few chapters or do you have to send off the whole thing?
Most people say you should at least complete the first draft of your book before sending it off to agents. Otherwise, if they like your first 3 chapters and ask to see more you'll end up in the slightly embarrassing position of having to say "Um, can you hold on for a bit - I haven't written it yet". It's better to finish the book first, especially as your synopsis may change as your novel progresses.
p.s. Some very good advice here Writers and Artists Yearbook