The number of websites devoted to financial matters probably exceeds the number of books on the subject.
Finviz.com is a free/subscribe site that allows a significant degree of interaction within the data sets included. A visit there is well worth the time spent learning the process. Any number of categrizations of stock can be developed and saved for monitoring purposes. It subscription servcie allows very advanced back testing trials and lst maintenance strategies.
Quantumonline.com is the reference point for all investments geared to retirement income. It is free/contribution. The education available here is immense, especially for the investor who does not have professional expertise. Lists of a wide variety of income securities are maintained and cross-linked. Prospectuses new and old are there. Tables of investments and definitions are abundant. Each publicly traded security has its own website and the 'investor' tab therein can be helpful for down loads, tax information, simple historical data.
Dividendinvestor.com offers a subscription service for the income oriented stock picker. Category lists allow distinctions between types of stocks: REITs, MLPs, CEFs, ETFs, Canaian royalty trusts. Each list can be worked for a variety of structural differences.
Dividenddetective.com offers a similar structure as a free/subscription service.Harry Domash has been compling this information for some time and the website is very user freindly. It offers free education emailing, as well.