Andrew, first time going international and first time planning a trip? Sounds so exciting! take a look at the blog I post a link to in your last post, there are some great articles and tips.
Having a book to right it all down and plan is a great first step. Make a list of places you want to go. Have a budget that you plan to stick to. Then go from there. look at travel booking sights that offer all-inclusive packages like Bookit.com All-Inclusive. This may help with the expenses and give you some ideas of good places to stay etc.
When you do go on your trip, I highly recommend a travel journal. Carry it around with you and write down your impressions of what you see and expreince. The smells, tastes and sounds of your destinations will be things that you will want to remember from your trip.
Have fun and let us know how it goes!:D