I have an Eton G3 recently purchased which has an operators manual, but does not contain any references to the layout of the buttons etc. I would like a link to find out the correct use of the radio

The buttons are marked and the use of most of them is self-evident.
The number keys are used to enter frequencies (direct tuning).
Lock locks the radio and prevent changes (trurning ON or OFF, changing frequency, any function change is blocked)
Sleep sets a timer.
+, - go up or down in frequency, or when you are setting time.
U/LSB is for toggling Upper or Lower Side Bands.
Auto Up and Auto Down are for the automatic tuning system (scanning the frequency spectrum)
AM is for switching to the AM (medium wave band)
AM/Meter band is for switching to the Short wave bands, and FM is for Frequency modulation band.
VOL + and - increase and decrease volume levels

Page/time: It has 700 memory locations to store frequencies. These are organized in pages (maybe up to 100 pages). You jump to next page with that button. Used also when setting time . Please read the instructions.

F1 to F7 are used to select the day for the alarm. F1 for Day 1, Sunday, F2 for Monday, etc) You can set an alarm for each day of the week.
Reset to reset configuration
TZ/Line in TZ set time zone, Line In if you wan to use the speaker of the radio as the output device for a signal from some other radio, or MP3 player
The tuning knob may also be used to change the displayed value while setting time (I can't remember exactly. You have the manual)
Erase erasing a stored frequency or a page (Check that)
Copy see above.