I'm having a problem as I cannot change the font size in any of the templates, can anybody advise what to do?

btw, I've used font wizard, etc.. so I'm using the usual visual editor methods but there not working.

You should be able to change the font sizes in the "custom" CSS file that is included with the template package.

It may depend on the particular theme (or "template") you are using but, generally, you would change font sizes in the external style sheet, e.g. default.css.

VSD uses 1-7 as font size variables, so you should be looking for one of those numbers instead of the traditional 12pt or 14pt fonts you are used to. Hope this helps.

OK, we were posting at about the same time...
I haven't used the Visual Editor for ages, but if you don't want to make the changes directly in the css file, and prefer to operate in the Visual Editor window, you should be able to just highlight the text and then choose font options from the right-click menu.

Just a couple of notes that occur to me:
You should be aware that the HTML Editor is first and foremost a code editing program. The use of the Visual Editor is not really recommended and that is why the Visual Editor tab is hidden by default.
If you really prefer to use a visual editor, the way to go would be the CC Visual Site Designer program.
An alternative approach, which many use, is to use the Code Editor in the HTML Editor in conjunction with the preview window on split screen (go to View > Split Screen, or just press F12 from the Code Editor). That way you will get instant, visual feedback for any code changes you make in the Editor window.

Thanks, what I meant is I used the visual editor as a last resort.
After playing with the CSS sheet, I've managed to sort the problem - thanks again!