Another learning question about resistors

Well...I appreciate the info but I am still stuck.

According to DipMicro they even say refer to the manufacturers datasheet. LOL the only problem is that I do not see it. The manufacturer is listed as generic.

According to the product page it gives the Forward Voltage and Current Rating (http://screencast.com/t/Pzl0Xnz7)

The product page is here White ø 5mm Clear LED Extra Bright 20,000mcd - dipmicro electronics

Is there a way to use my tester? I can measure volts perfectly (well for me that is). But I cannot quite figure out how to test Ohms.