There are many antenna-focused Yahoo groups you could join and then post them there. The ones I've joined are Amateur_Radio, Antenna_Builders, Ham-Antennas, HamRadioAntennas, LoopAntennas and SkyWires. All of them have areas to post your work and/or picture(s) you have to share with the group(s) you join. Another way would be to build your own website. I believe you can build a URL for free in Google. Some folks have. I searched
https://sites.google.com/?pli=1 and found some ham sites there. I'm sure there are other places on the Net for free URLs too. I just don't know of any other than Google.
BTW, I'm researching deltas. I want to build one for 10 and point it towards the countries of the western Pacific Ocean
I hope I was of some help.
73 & GL
Greg K3ANG