Welcome newbie!
My first piece of advice is read & learn. The best book in my opinion is Speaker Building 201 by Ray Alden
http://www.madisound.com/books.html. I've tried to read Vance Dickason's book and it is too hard - not the subject matter, but the writing. Alden does a better job presenting things clearly. I tend to overlook the speaker designs in his book because they are now or will be soon out of date in the sense that some of those drivers will be hard to find for sale. Also I prefer to stick with designs that I have heard or are designed by people I am somewhat familiar with.
Avoid using stock crossovers. Too many eager newbies think that all they need is an imagination, a Parts Express catalog, and a circle saw. The whole benefit of DIY speaker building comes with using crossovers custom designed for a set of drivers in a particular cabinet. Crossover design is the most difficult part and the most rewarding part. Second in importance is having broad experience in listening to a wide variety of speakers and individual drivers. Thats why I urge you to follow a recipe from an experienced designer. These are some DIY designers, who have good websites with a large variety of designs, that I would recommend:
Dennis Murphy
http://murphyblaster.com/content.php?f=main.html He is my personal favorite - see more below.
Lou Coraggio
http://www.lonesaguaro.com/speakers/ Lou Coraggio has some very interesting designs, although I've never heard them. His woodworking skills look very good. That's always something to strive for.
Wayne Jasche
http://www.speakerbuilder.net/web_files/default.htm He has some articles on his site that helped me learn quite a lot when I was starting. See his article titled "Finding the Optimum Crossover Frequency". His designs tend to use less expensive Dayton drivers.
Roman J Bednarek
http://www.rjbaudio.com/ Like Dennis Murphy, Roman likes paper coned drivers and textile tweeters. The more I read of his stuff, the more interested I am in his designs. He seems to like drivers that I have heard and know that I like. I am especially interested by his Asterion design.
John Krutke
http://www.zaphaudio.com/ John Krutke, on the other hand, loves metal coned drivers. He also has a lot of test data that can be interesting, although some of it is above my head.
All of the above write well and present reliable info in a form that I can easily understand. All of them test their designs carefully both by computer modeling and by real world listening.
All of these guys, except Wayne Jasche, will answer your questions if you email them, or if you post on the Madisound discussion board
http://www.madisound.com/cgi-bin/discuss.cgi. This forum is the best DIY speaker builder hangout.
I've built 2 of Dennis Murphy's designs (the MB20, a 2-way for about $320 a pair, and the CAOW1, a 2-way for about $450 a pair) and I can highly recommend both. I built the CAOW1 in November and it is now my favorite speaker. The MB20, I built for my nephew in Los Angeles, is a less expensive version of the CAOW1. Both are small cabinet 2-way ported speakers with a 5¼" midwoofer and a 1" (in the MB20) or a ¾" (in the CAOW1) dome tweeter. Both use 2nd order crossovers which Dennis believes contributes to a more open and spacious sound. I tend to agree. I was actually impressed by the unexpected bass response of these small speakers. The CAOW1 can deliver an honest 50 Hz, the MB20 (and its cousins the MBOW1 and MB27 that use different tweeters) delivers an honest 55 Hz. Dennis showed me what baffle step compensation does for small speakers. A lot of commercial small 2-ways fail to address this problem at all! To learn what BSC is see
http://www.quarter-wave.com/General/BSC_Sizing.pdf. The tweeters (Hiquphon OW1s) that are in the CAOW1 and the MBOW1 designs are without any doubt the best tweeters I've ever heard. They cost $200 a pair! That's why Dennis also offers the MB20 and MB27 that use tweeters that go for about $60 a pair. They are also quite good.
The bottom line with Dennis Murphy's designs, is that I like the way he "voices" his designs. I like their sound. Not surprisingly, his designs also have quite flat frequency response curves. I have met him, he lives in my area. He is not an EE, he has a Ph.D. in economics! He is an amateur musician (piano and violin), and he has the best listening acuity I have ever witnessed. He has about 25 years experience in DIY audio, and his expertise in crossover design is highly valued in the DIY world. I have come to trust all of his audio choices. Your taste may certainly vary from mine.
The vendors I've used are Madisound
http://www.madisound.com/, Parts Express
http://www.************.com/ and Zalytron
http://www.zalytron.com/.
You mentioned a little of your background. What woodworking experience and tools do you have? Large savings can be made by building your own enclosures. Your woodworking abilities may well be the deciding factor in what your first project should be. Small cabinets such as for a bookshelf speaker are easier to do for a beginner and require less elaborate woodworking tools. Towers and subwoofer cabinets often require a table saw. In the sense that subwoofers don't require a separate crossover, they are simpler for a newbie to make as a first project. They do require a properly crossbraced cabinet.
I think, I'll stop here and let you digest some of this.
