Obviously if you're only submitting a book proposal, then you'll probably only be sending in a chapter or two when asked for it and not an entire manuscript. But should you be asked for the manuscript in its entirety, this is how the title page ought to look. Some people will place the title a third of the way down the page, but most will place it dead center. Place your name/address information on the upper left side and the word count on the upper right. This is the only place in the manuscript where this information should appear, and it should be single-spaced. Everything else on this page, like every other page in your manuscript, should be double-line spaced, and a proportional font should be used. You can never go wrong using Courier. (In MS Word, this is referred to as "Courier New"). Almost everyone uses Courier. This may look a little odd to you at first, but if you print out a few pages of double-spaced Courier text you'll soon get very accustomed to it. It's very easy to read, and it leaves sufficient room for the editor to make correction marks between the lines.