By now you should have the logo design finished. The final stage is to convert the same logo into different formats so that they can use it in the future for a range of different applications.
Start with the Pantone design - save it on a page (about 120mm x 120mm), put an clear and invisible box around it to give it some space (also this will make sure that it crops in properly when calling into other programs like Indesign.) Save as an .eps file. Convert the logo to CMYK colours - you will need this when designing material for printing using 4 colour process, save as a seperate .eps file with a different extension name. Then open your original Pantone file and convert the colours to RGB you will need this for web site design and anything viewed on-line or on-screen. Make sure you save a black version too (.eps)
You also need to save the files in a jpeg and/or bmp format too - this will simply be a picture image of the logo. Open the RGB eps up in Photoshop (or copy and paste from illustrator to Photoshop) and save down as both high and low resolution jpegs and bitmaps (high for print, low for web). Also its advised to do the same thing to the black logo.
So now you have the logo set. It might seem a long process to get all these file types together but it will save you time in the future, when you may want to do business card design or when putting the logo onto a letterhead design.... it's there, ready to use! Save everything into the relevant folders, zip it up and send to the client.