Among the 4" .38's I know of, ones I've considered recently are Ruger's GP100 and Smith & Wesson's 620. They're both reliable, with the GP100 being the cheaper one. A 4" steel revolver is a bit big for most types of carry, but I do it occasionally.
Personally I lean towards the GP100; I own the smaller Ruger SP101 and S&W 642, and the Ruger seems better built, but that's my taste - Ruger makes their guns a little tougher while Smith makes theirs more elegant. The SP101 and S&W 640 are good choices if you're looking for something compact. (The 642 is basically the aluminum version of the 640.)
Most of these guns are all chambered for .357 magnum, technically. Finding a model that only shoots specials is a little harder.
Not too many 4" double-action revolvers come in .45. You mean .45 colt, right?. Ruger's Redhawk and S&W's 625 Mountain Gun are the only ones I can think of that are currently made. As far as stopping power's concerned, either .38+p or standard pressure .45 colt would do fine.
If I wanted a steel CCW revolver with a decently long barrel, I'd probably go with either a 3" Ruger SP101 or 3" S&W model 60. A larger revolver would weigh me down unless it was just for a day or two.