Dillard's stores carry Merrell's.
I wear Merrell's and love them. But, as a PP said, not every shoe brand works for everyone. I just did shopping this morning for some new Merrell's for our coming Disney trip. I want a few weeks to get used to them.
You will find the widest variety online. The 3 sites that I'm listing below have a huge variety of Merrell's and of many other brands. Also --- and this makes huge sense for purchasing shoes online ---- Shipping is free, and RETURN shipping is free for these sites. That allows you to purchase multiple pairs of shoes, knowing that you'll need to return some (or all) of them. You can try different sizes of the same style, or you might find several different styles or brands that you want to try. Try them all, and return what you don't want. Even the standard, free, shipping is supposed to be pretty quick. I haven't received my order yet, though, so I'm not certain.
Shoes dot com
Shoebuy dot com
Zappos dot com
You might find pricing to vary by $2 or $3 among the websites. This morning, I did see one style that was $9 less on Shoes dot com. I haven't often seen Merrell's on sale, unless it's clearance.
Also ---- I saw this morning that Shoes dot com currently has a 15% discount promotion going. But it isn't good on most of the premium brands, such as Merrell's.