These are all celtic knots that are generally called "Ceilidhs," which in Gaelic means a community gathering and celebration. It's pronounced, "Kay-Lee" Like me. ^_^ Possible tattoo ideas down the road
Great tutorial on drawing celtic knot borders. Celtic Knots 101 - Running Borders - WetCanvas
Tree of Life Infinity Tree Wall Decor Wall Art
Tree of Life Infinity Tree Wall Decor by HumdingerDesignsEtsy, $240.00:
Celtic Knotwork inspiration: Celtic Knotwork RW Series 02. In no way do you have to use any of these, though if you find one that inspires you....go for it!
Not a dragon, but really cool. Oval Tribal Celtic Knot - Dreaming Dragon Designs - Printfection.com