1. I would practice, a lot. I do think some of your images have potential. Would I buy them? Not right now, because I can go out and take that same photo and make it better. I realize you are shooting in auto in some of the photos, but I'd look into getting Lightroom, Photoshop, etc. If I'm looking at a photo to buy, I want it to look professional.
2.I would check into finding a professional printing company like White House Custom Color, ColorInc, etc...to print your photos with. Browse sites like Etsy, SmugMug and see what other artists are charging for their work.
3. Selling photos online can be difficult. I've sold for two years on Etsy and have sold about 30 prints. There are so many different photographers and artists out there that you really have to be patient, get your name and work out there and be noticed before you see any of your prints sold.
4. Don't shoot something that anyone else can, if you do, make sure it's captured in a unique perspective. One thing I look for when I browse for photos to buy is 1. Is it a place I've been and they captured it different? or 2. Is this someplace I haven't been and would like a photo of it? I lived in Europe for a few years, so a lot of places, I have my own photos of, so I don't feel the need to buy those from others. I look for the unusual or something I don't have or can't take a photo of myself. Make sense?
Canon 18-55mm | Canon 10-22mm | Canon 70-300mm | Canon 50mm
"A true photograph need not be explained, nor can it be contained in words." - Ansel Adams