Your best bet is to write the script and sell it to the studio, then lobby the studio to make you a director. The only problem with that is that you have just sold a property that does not belong to you, as the owner of the rights to the material has not given you explicit rights to option the source material to be translated into a screenplay.
Your best bet is this -- you, the screenwriter, need to offer the rights owner (the author) a one-year option on the material at around 10%, or another agreed upon price. What this means is that if you option the book for one year at $10,000 for the rights, you the screenwriter only need to pay the author $1000 up front. If the script gets bought by a production company, they purchase the option for the full amount -- the studio pays the rights owner the balance of the option ($9000), and the script goes into production.
The script must begin shooting within the year, otherwise the rights owner retains the fee that you agreed upon and the rights revert back to the original owner.
This is one of those cases where you, the screenwriter, either need to find a producer willing to put up a little money or put the money up yourself to purchase these rights. Remember, $$$ is the magic word. Whether this actually gets turned into a movie or not, the rights owner gets paid.
Once you own the rights to the project, you can legally start shopping the screenplay around to studios and other producers, building capital and working on attachments to the material (the screenplay).
First thing you need to do is find out who actually owns the rights to the material (the book). Almost always, the publisher of the book owns the copyright and all reproduction rights to the books. If it is a small publisher, then the author may have purchased the rights to their own book. If it is a large publisher like Random House, all I have to say is good luck getting the rights to any of their catalogue without having sold at least three screenplays that have been turned into movies already. If you are lucky enough to get a publisher and/or author who is willing for a price, then do it.
But, the number one thing you need to do -- hire an attorney! Property rights get very sticky when moving between media formats, and the contracts can get very weird and convoluted. Hire an attorney to help you through this process. The only reason I know what I do is that I work in a law firm, and my mother is an attorney who does entertainment law. And all entertainment law is -- it's contracts. So, my best advice, get an attorney!
Now, as far as attaching yourself to direct, that's tougher. Where you hold the rights to sell the screenplay, you can also include in your option agreement with the studio that you be attached to direct. The problem with this is that as an untested director, most studios would balk at the idea. Now, you can hold out if you want to. The problem is, your script better be damned good and you better have the cojones to face a lot of rejection as a director. A lot of people will tell you that they like your script but, since they hold the power, why should they be threatened by you? There are thousands of new directors and screenwriters to choose from out there.
Go out and read the book "Down and Dirty Pictures" by Peter Biskind. He devotes an entire chapter to Matt Damon and Ben Affleck trying to sell their script for "Good Will Hunting" as well as attaching themselves to star. Same as what Sylvester Stallone did in "Rocky." But, these are the exceptions to the rule. Where they wanted to act -- whether they were good or not could be deduced from screen tests that are cheap to produce and quick to return results. Where you want to direct, ay, there's the rub. It costs a lot of money to even see if a director is a good director and, if you do not have a solid directorial background or the confidence of a major player involved with the deal, this is harder to swing.
I'm not saying don't try it. I'm just saying keep expectations in line with reality.
Your last big problem is a combination of your other two: you don't want to write the script unless you know you're going to direct, and you can't write the script unless the author (who, at this point, I assume is the rights holder) gives you the option, and he won't do it unless the money is in place. This may just be one of those times that you have to bite the bullet and settle for less, or hold off completely. The author can't expect you to sell a book, because you are in the business of selling screenplays. You have to communicate that with the author. And nobody is going to give you money to do a movie without seeing a script. You either need to put the work in, write the script, and show it to producers or not do the project at all -- put it in your little book of things to do when you are a rich and powerful Hollywood player. Of course, depending on what comes along, someone richer and more powerful than you may swoop in and take this book that you are so keen on. It's your call.
I would write the screenplay, get producers interested enough to show the author that there is interest, and then sell the script (with the option from the author originally in place already). I would not worry about burning the "attach as director" bridge until that battle is worth fighting, because now is not it. Get the script sold!
