Kendall, let me see if I can shed some light on the subject for you.
Texas PPA is a state affiliate under PPA. The five states of Arkansas, Louisiana, New Mexico, Oklahoma, and Texas make up the Southwest PPA which is a regional affiliate of PPA. If you are a member of any of the five state PPA affiliates, you are automatically a member of SWPPA at no additional charge. The annual dues to be an active member of TPPA is only $85.00. As a member you will receive six TPPA magazines a year, free registration to the Annual Convention, and reduced member registration at our Summer Seminar.
Professional Photographers of America (PPA) is the umbrella organization over the state and regional affiliates. The annual dues for a PPA active member is $323.00 and for an aspiring member is $194.00. These dues include indemnification insurance which means that PPA will come to your defense if you screw up a job, or your hard drive crashes with the only copy of a wedding's files, or many others instances of contract fulfillment disputes. It is similar to medical malpractice insurance. For other PPA benefits click this link:
http://www.ppa.com/i4a/pages/index.cfm?pageid=665
PPA holds one national convention each year and there is an additional charge to attend the convention. The 2009 convention will be in Phoenix, AZ., 2010 will be in Nashville, TN., and 2011 will return to San Antonio, TX.
There is one other level of PPA affiliates and that would be the local guilds. Most of them meet once a month and have dinner and a program. This is a great place to network and build relationships with photographers in your area. There are local guilds in Tyler, Waco, Houston, Austin, Lubbock, Wichita Falls, Ft. Worth, Richardson, San Antonio, Texarkana, McAllen, and College Station. The TPPA website:
http://www.tppa.org has links to most of these local guilds.
I am a member of all these organizations and I advise new photographers to start by joining their local guilds if they have one near them. If you can afford it you should also join your state affiliate. However if you do weddings you really need to be a member of PPA.
TPPA has only one paid employee to oversee almost 2,000 members so most of our work is done by volunteers. Our website was created by a volunteer back when websites were still a novelty and you had to be able to write html code to create one. It has served us well and we are looking at an update in the near future.
Thanks for all the input and I hope I was able to give you some useful information.