I have a half acre lot on Dolphin Way (actually 3 lots) with a good view of the Gulf. They are close to Linda's bait camp with paved frontage. Price is $27.000. I have the survey and appraisal done already.
Your best bet is just to take a drive through the area. There are plenty for sale. It's just a matter of what you want. We have a lot on Carancahua(CR201) on the opposite side of the street between Charlie's Bait Camp and Linda'sBait Camp that is on a canal. Two down from us is a lot for sale. There are three main players as far as realtors. Already mentioned was Gulf Coast. You also have Remax and Full Stringer that have quite a few. I found one that I was able to buy directly from the owner which allowed me to buy at a better value. Look carefully. Quite a few of the lots are easily flooded with rains and tides. You might also look at http://www.sargenttexas.com/board they have a classified section that might help.
Yeah the canals are accessable. Be aware that the canals are pretty narrow and the lots pretty small. I would look for a property on caney creek. Thats where we bought our place and its alot nicer. Plus the fishing can be awesome with some good tides.