Computer Science 

Anyone can put up a web page, so it's important to view web sites with a critical eye. Keep these criteria in mind when using the web.

1. Accuracy:
Who wrote the page and why?

2. Authority:
Is the author a credible source? What are their qualifications?

3. Objectivity:
Is there an opinion expressed? What is the goal of the page?

4. Currency:
When was it last updated? Are there broken links?

5. Coverage:
Does the page cite its sources? Is the information comprehensive?

The domain can provide more information on the site:

.edu = educational institution
.gov = US government site
.org = organization or association
.com = commercial site
.museum = museum
.net = personal or other site

arxiv  
Open access to 535,728 e-prints in Physics, Mathematics, Computer Science, Quantitative Biology, Quantitative Finance and Statistics

CiteSeer.IST 
Allows users to search for computer related topics. It provides an abstract of the article and the number of times cited. Many articles are full text pdf.

Collection of Computer Science Bibliographies 

CoRR 
Computing Research Repository (CoRR), sponsored by ACM, the arXiv.org e-Print archive, NCSTRL (Networked Computer Science Technical Reference Library), and AAAI.

DBLP
Digital Bibliography and Library Project collects information about CS conferences and journals; currently indexing more than one million articles.

io-port.net
Access to more than 2 million publications in informatics and related subject areas.

Libra 
Libra is a computer science bibliography search engine from Microsoft. Also serves as a test-bed for their object-level vertical search research.

Science.gov Computers & Communication 

Scientific Commons: A Community for Scientific Information 
The site has indexed over 13 million open access documents.

Scitation 
Over one million documents from scholarly journals, magazines, conference proceedings, and other special publications from prestigious scientific societies and technical publishers.