Hi Joanie,
Congratulations! Getting married in Aruba is a beautiful experience and you can make it as simple or as elaborate as you wish. Since you got engaged there, I think it sounds like the perfect place to return for a marriage and honeymoon! (Or what I like to call a wedding-moon!) Just think how beautiful your wedding pictures will be! I'm one of those people who likes to do things differently, so getting married in a tropical destination was a perfect choice for us. Some people hire wedding coordinators/planners and this is probably a good choice if you want a larger event with several guests coming in for the occasion, and want to have a reception of some sort. We kept ours simple, just the two of us, and I was able to plan everything from afar via email and a few phone calls. All we really needed was someone to perform the service, a photographer and some flowers!
There are no blood tests required, BUT you can't get married at the spur of the moment. I planned mine fairly quickly (a few months) but that is pushing it. You will have to gather some documents (birth certificates, passports, copy of divorce decree if you were married before...) and get them approved by the Aruba Registrar about 30 days before you want to get married. The hardest thing for me to locate was the "Letter of No Record". It took a while for me to find someone who knew what the heck that was, but once I contacted the right department (in Ohio, that is the Dept of Health, Vital Statistics Dept), I got it within a few weeks. It is basically a record from your state saying there is no current record of marriage for either of you and that you are free and clear to marry. It must be accompanied by an Apostille seal, which comes from the Secretary of State and verifies the authenticity of the document.
The link below will give you specifics on everything you will need.
http://www.aruba.com/specializedvacations/honeymoon.php Click on the "click here for marriage requirements" link from there.
I hope this is helpful in your planning. If you have more questions, post them here - everyone is very helpful and knowledgable. I've only been to Aruba once, so I'm no expert, but I'm glad to share my own experience. You can also send me a Private Message here, if you'd rather.
Good luck and let us know if we can help!
Lori