i have an etrex 30 myself (the 24 channel receiver appeals to me soome to be accurate right away even under bridges and in valleys)
and a 10 year old etrex without sd slot this holds only 500 catches
i loaded all these(it was at its limit) into the etrex 30
I was a bit worried so found an sd card 2gb
the hand held unit works with SDHC card so unless there is some sort of arbitrary limit you can do far better than a 2Gb max SD card smallest sdhc card is 4Gb
I have the usa relief maps on the 2G card and havent overflowed yet
try the garmin site a lot of people there have done things
There are some exceptions that are strange in the garmin catalog (like SD rather than SDHC)
the forum there has a lot of stuff where people push the limits
