I love, love, love the book Healthy Sleep Habits, Happy Child too. But...you may also have noticed in the book that you really can't expect to start any sort of real pattern nor should you try CIO until 4 months at the very least. At 2 months our son was all over the place with no consistency to speak of. We did let him sleep in a vibrating bouncy seat in his room, which led to longer stretches of sleep at night. There were nights that, in the seat he would sleep 5-7 hours. At 2 months it was awesome! At 3 months we transitioned over to the crib and used a sleep positioner and it worked wonders. We were also swaddling, which helped.
We did not choose to start any formal sleep training until 6 months, but when we did, we followed the techniques from the book to the letter. Quite literally it took 3 days and he was on a schedule. He was much happier during the day, napped better and slept better.
Just a warning...you are going to get many responses on here that will say you are an awful mother for wanting to use CIO and others will say you're an awful mother for co-sleeping. Both methods have their merits, but you really need to think long term about your family situation and what techniques will apply best to your circumstances. Personally, I would suggest that if you know you do not want to co-sleep for much longer then you should move away from that technique. I'm not saying it is a bad habit; I'm just stating the reality that the longer you co-sleep the harder it will be for you to change patterns and have the baby sleeping in a crib. Also, since you're going back to work you have to ask yourself how the child care is going to handle the napping. Will they hold her for hours on end like you do to assist her in sleeping or are they going to put her in a crib or a swing to sleep? Are they going to be 100% respectful of your sleep techniques and implement them just as you would at home or are they going to do things their way (ugh!) despite your instructions? The answers to these questions will probably best guide your decision making when it comes to napping/sleeping.
Good luck to you with whatever choice you make. And no matter what anyone tries to tell you, CIO is not abusive just like co-sleeping is not spoiling. None of us have walked in your shoes and have to live the life you do :)
And...if you have questions or need some help with Weissbluth's techniques, just send me a PM. I'm happy to try to help!