I think the PhDs.org website (http://www.phds.org) has some good resources.  It offers customized "rankings" based on student priorities and data from the NRC and other sources. There is also an extensive collection of links to external sites offering advice (and opinion) on why grad school, how to get in, getting through, and what comes next.  

I compiled a list of internships a year ago. It's by no means complete, but one good place to start is the NSF site where you can search REU sites. You could export a listing of these.

I think matt.might.net has a lot of useful (and sometimes painfully frank, and maybe a little too honest or overly harsh) articles from the viewpoint of a professor looking back on the journey and also someone who has reviewed applications to grad schools and mentored young PhDs.  See what you think.

http://matt.might.net/articles/how-to-apply-and-get-in-to-graduate-scho…

http://matt.might.net/articles/phd-school-in-pictures/

http://matt.might.net/articles/ways-to-fail-a-phd/

In terms of applying to schools and life beyond the undergraduate years, I've given this advice to undergrads in our lab as they were applying earlier this year:

Go somewhere where you think you will be happy living for 5+/- years. Not just a good school (and you do want to get into a good school), but a place near things you enjoy. Like hiking and mountain climing? Go to a school near mountains. Can't imagine living away from your family? Go to a school that is close enough that you can see them regularly. Like going out and enjoying music and art? Go to a school in a city with a vibrant music and art scene. These things matter, because you will be working there for the whole year and living there, you don't have summer break like you did in college. Grad school is very challenging and can be very stressful (in very different ways than college), and you want to have healthy outlets for getting through the tough times. If you did sports in college, continue to do the sports that you enjoy.

Also, apply to schools where there are at least 2-3 profs whose research really interests you. You never know if that 1 prof you think is really cool gets hired away to a different school, accepted too many students and have no room for you, decides to retire if they are later in their career, or they don't get tenure if they are early in their career. These things can and do happen.

Ask your college professors about the specific profs you are interested in, especially with regards to how they run their labs and the environment in the lab. When you visit the schools, ask the current grad students the same questions (when they aren't around professors or senior students/postdocs). You want the real scoop before you make a decision.

Also ask where the graduated students went after they are left. Some labs can look really great from the outside, but then the students don't go on to good jobs in academia and industry. Even though its 5-6 years away, where you can go after grad school is an important part of grad school. You want to be sure that if you work hard and produce for your advisor, you will get a good letter of recommendation.

In terms of your future career prospects, find out how the group publishes.  Does the prof write the papers or do they let students write them (I prefer that students write them or help write them in grad school, because it helps teach writing skills)? Does the prof publish a lot or a litte? Is there a specific publication requirement for graduating (I know of profs who have said "you need 5 1st author papers in top-tier journals before I will let you graduate")? Does the prof collaborate much (collaborating can be great for networking opportunities for future jobs, and a way to learn more about the chemistry field as a whole)?  Make sure that you are satisfied with the answers to these questions and clearly understand what that means for your grad school career before you join their group. 

-Kyle