welcome to the forum! I've just read through your information. I think you've come to a great conclusion - having a sump will make life so much easier in the long run. Checking the local listings is another great option and you're already doing that. That you have woodworking skills can only be an asset in this hobby! I love clown fish and kept a fish only tank for many years when my kids were little - it's a lot less work than a reef tank. I would suggest you check out some of the designer clowns - so you have an overview of the different types that are available. Once you settle on your clowns (a pair is preferable) they will most likely be with your for years. There are many colorful and interesting fish in this hobby - you can check out diver's den on the web to look at the different varieties that are available. Try not to get damsels (although clowns are damsels) - they are colorful, cheap, but can be very aggressive. Diver's den also gives information about eating, hardiness, and optimal tank sizes for the different varieties.
Welcome to this wonderful hobby! I think most of us have started in freshwater so that background will also be an asset to you.