Um well according to economic theory i would say that none of it is overpriced. Intel/AMD are going to charge what they think will bring in the most revenue, and as long as customers are paying for these expensive components there won't be major price cuts. All in all it's the customer population's fault that some of these prices get so high. Think about it this way: there wouldn't be a $1000 extreme edition processor from Intel unless there were enough people out their buying them to keep the processor profitable enough for production. If we as consumers want lower prices on the expensive parts, we will have to show that price is a very important factor in a sale and that we are willing to sacrifice some performance if it means saving a good chunk of cash. Another way would be to have more competition in the market such as a third, but smaller player in processor manufacturing for pc consumers.
However, do i think that you are throwing a ton of money away buying these processors? Yes, i do. The hot topic today (or was for a while) is the i7 920 vs. the i7 965 or even 940. With the latest revisions, it is extremely easy to get "extreme" performance out of the 920. Therefore, even for most hardcore users i would say the 920 will more than suffice. Save yourself $700 and go with the 920, or save a little more by going with a new phenom from AMD. It all depends on what your needs are.
Having a monopoly is a completely different story though. I know a lot of people probably would like to accuse Intel of this, but i will stay out of that argument. Intel having a monopoly would mean that they can charge whatever they want because the consumer doesn't have any other option other than ditching a new computer all together. I would say that this cannot be the current case though with the popularity of AMD. I would say AMD and Intel both share a slice of some sort of monopoly.