For a .38 I'd probably recommend one of the .357 revolvers from Smith & Wesson ( shoot .38's or .357 mag in it ). I like the older Smith revolvers - model 27 in a 6" barrel is one of my favorite guns.
For a .45, I really like the Wilson Combat - close quarters battle - it's a very nice gun ( no trigger job required ) and its a gun I shoot a lot. If you find a good used Les Baer in a shop take a good close look at that too - his guns are first rate as well.
Kind of depends on what type of budget you have - I'm also a big Sig fan ( 226 X Five and others ).
One thing to consider is that .38 is more affordable to shoot than .45. I'd recommend an older S&W from before the internal lock. They just don't look right with that thing on the side. I can recommend a place to look for used S&Ws if you're interested.