While designing my site I am constantly faced with the issue of whether its ok to TAKE ideas and designs from other sites. In some cases there is no distinction in certain aspec
Stealing resources (graphics, code) is not really OK if they're not specifically marked as free/open/creative-commons/etc. Stealing design and layout is a bit sketchy if you're just xeroxing the same layout using your own code -- using someone else's design as a starting point is one thing, but don't just recreate their design verbatim. Stealing snippets of code for specific bits of functionality is fine (IMHO) since even if you grabbed a reference manual to learn it from scratch you'd end up with the same thing. (Think: javascript for changing an button image on mouse-hover)
Having said all that, imitation is the sincerest form of flattery. Don't steal resources, but using other sites as "influence" should be OK. Or, if in doubt, ask the owner of the site you intend to use as reference/influence.
It's almost like everyone answering this question forgot what it was like to work with web pages between 1995 and 2002 or so. Stealing was a way of life for tons of designers during that period. The key was, and still is, to take only what you need, and to make sure that you understand it well enough to make it from scratch the next time. Who knows, you might improve something in the process.
Oh, this is a hard question.
On the one hand stealing is wrong, on the other hand you are obliged to save you employer money by solving a task quickly.
My only advice is: If it feels wrong in your gut, you probably stole too much.
For the most part, ideas are fine to take and implement. If people couldn't take existing ideas and expand them or re-implement them, we'd never have gotten out of the dark ages.
If you feel the need to steal code because you can't code HTML/CSS well or don't have an eye for design, steal from a place that explicitly permits you to use their design/code, like OSWD. In general, stealing HTML is fine, but ripping off CSS wholesale is a no-no. Just because you can easily view the CSS source doesn't mean that it's ok to just copy and paste it.
Don't steal graphics, period. Especially things like photos and logos and icons. If you need that sort of thing, purchase stock photography or take your own photos.
When in doubt, ask the owner of the site.
This is how a lot of design is accomplished. Except it's obscured by lots of lifts, not a single wholesale lift.
I think most designers and developers draw a distinction between 'creative inspiration' derived from someone else's work and blatant plagiarism. I wouldn't think twice about peeking under the hood to see how someone had done a particularly nifty javascript effect, or implemented a tricky piece of css elegantly, but I'd find it distasteful to blatantly cut and paste that same code for use in my own development.
I'm not learning anything by just grabbing and reusing - although I think it's fairly standard to have the same code to hand as a rough scaffold from which to explore my own way of implementation. I think that's the way a lot of people work.