Tables are still the easiest way to control the layout of a page. It is a good idea to use percentage to size them rather than pixels. If you design tables using pixel width, someone using a display of 640 x 480 will have to scroll across as well as up and down, this can be quite annoying.
Although tables are a good tool they can cause problems for text only browsers, a page of text kept clean by tables could be pretty incomprehensible in a text only browser. The most important thing to consider would be the use of columns for text, as in a newspaper style layout.
Try using the Lynx viewer to check a page using tables, see how it reads tables and displays them and how it handles graphics.
Divide up long tables, a browser will wait until it's got the whole table to show it, the difference in the style of the page is minimal and it can make a lot of difference if the page holds a lot of information.