If you do decide to eventually go through with it, then some things you should know-
Shop around for the artist you want. Most shops have multiple artists, and if you show the guy answering the door and phone what you want, they should be able to tell you which guy/gal does that style.
Remember, these are artists, and they all have different styles. Ask to see their portfolios. You should be able to tell quickly if what they specialize in is what you're looking for. Look especially close at their coloring in the "after" photos. Once the tat heals up, you'll be able to tell any spots in the shading that are lighter or darker than the rest. Nothing like ruining a solid color area with crappy shading. You can have that fixed, but it's never quite perfect unless it's done right the first time.
Don't be intimidated by the old stereotypes of tattoo artists. Most of em are just regular folks who like ink. Yes, the 400 lb'er in the corner with 15 nose rings looks like a scary mofo, but he's usually a decent guy.
Expect at least 75 bucks an hour (usually 125 for real good work). I remember the pic you're thinking of, and that looks like about 3-4 hours of work easily if you're thinking about 3"x5" for a bicep. You can have it done in multiple sessions to break up the cost if that's an issue.
The advice above about hanging the pic somewhere you see it every day is fantastic. Tattoos are not for everybody. However, I have 2, and love them both. I thought a lot about both of them, and they will always mean something important to me.
Tattoos are addictive. Ask Dusty_C.