I don't know exactly what frequency tables are, even after my stats class circa 1988, But I know that if you need them, you need them. Here's a nicely explained and illustrated blog about using them in OpenOffice.org Calc, from Ernest.
Here's another link that Antonios tipped me off about. They're for Excel but I understand they also work in Calc.
Lightweight data exploration in Excel "We often are given a chunk of data in Excel that we need to explore. Of course, the first tool you should pull out of your toolbox in cases like this is the trusty PivotTable (it slices, it dices!). But at times we have to dig a little deeper into the toolbox and pull out the in-cell bar chart. "
More on Excel in-cell graphing "We received an enthusiastic response to our post on in-cell bar graphs in Excel. The community quickly explored every edge case. I want to highlight some of the great ideas raised. Henk was first out of the gate with a great suggestion that two columns could be used to show positive and negative values. "