Don't waste your time or money chasing titles that other people think are rare or may be worth a lot of money someday. The fact is that nobody can accurately predict how sought after a book will become in the long run. A book's value will go up and down over the years. If you collect only books you love, you'll never be disappointed when (not if) a title you own doesn't live up to your financial expectations at any given time. Also, when the Famous Five book you've had since you were a child turns out to be worth five times what you thought, your satisfaction will be that much sweeter!
2. Essential Advice for the new collector
I know I just said that you shouldn't collect a book for it's investment value and I stand by that statement. However, although your motives are not tainted by profit, it certainly doesn't hurt to buy a book that's more likely to see a price increase. So, keep in mind that, with few exceptions, early (preferably first) editions in very good or better condition trump book club editions or any copy with its spine missing and the last chapter ripped out.
3. Learn how to spot a First Edition
This is not as simple as it should be. I will cover the subject of How to spot a First Edition in it's own posting here on my blog in the coming days.
4. How to Store Books Properly
We cover this in great detail within our "How To Store Books Properly" posting: http://rareandsigned.blogspot.com/2009/11/how-to-store-books-properly.html
5. Mini & Formal appraisals
This is important as you do not want to be ripped off when you buy a rare book and it is also good to evaluate what your own collection is worth. We have created a posting on our blog to show you how to appraise a book in detail: http://rareandsigned.blogspot.com/2009/11/how-to-appraise-book.html
For further help and advice specifically on collecting and identifying your book collection visit our website at http://www.rareandsigned.com/