For basic stuff; the Chilton or Haynes are ok and cheap at under $30 apiece. However, they both can too basic for many things you need to know (lack of depth and pictures, info etc.). The Bentley eBahn software version has more in depth coverage or you might get Erwin online subscription for one day and download all the manuals you need.
The downside of the eBahn software; is that it hasn't been updated for later versions of Windows and so, you have to do some workarounds, to run it on later version of Windows (e.g. xp compatiblity mode).
Bentley, has lost its publishing agreement with VW; so, they will not be making new manuals and I do not know, if they are updating the content of eBahn (e.g. technical service bulletins, recalls, etc.). This maybe, the reason; they have stopped updating eBahn but I do not know, for sure.
Erwin is VW's subscription based solution; for the professional technician, so there is less simplification of repairs and you can download these in .pdf form. This can be less user friendly; as you have to search through the .pdf files but the information is superior, for the advanced diy or pro mechanic.
NOTE: Bentley has two (2) manuals: the paper version and the software based eBahn, the eBahn covers much more information then the paper version. The software based subscriptions; give you access to tech bulletins, current updates, campaign info and other resources, that you will never get with a paper based manual.
eBahn Bentley license (download from the web; cheaper price then DVD)
eBahn License for Volkswagen New Beetle 1998-2009 Ă‚*-Ă‚* Bentley Publishers - Repair Manuals and Automotive Books
eBahn Bentley repair manual on DVD (hard copy sent to you)
Volkswagen New Beetle: 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 including Convertible Repair Manual on DVD-ROM Ă‚*-Ă‚* Bentley Publishers - Repair Manuals and Automotive Books
paper service manual Bentley
VW - Volkswagen New Beetle Service Manual: 1998-2010 Ă‚*-Ă‚* Bentley Publishers - Repair Manuals and Automotive Books
Erwin subscription based manual: downloadable .pdf based files
https://erwin.vw.com/erwin/showOrderFlatrate.do
The other option; is free manuals online here:
Volkswagen Workshop Manuals
Some manuals; are sold on ebay on dvd or cd rom, these typically are copied files from professional digital manuals and are similar to the above free manuals.
So, you might start out with a cheap Haynes/Chilton and see if it meets your needs. If you need more indepth info; consider the Bentley paper for good repair info but without very in depth repairs (e.g. tranmission repair, etc.) or eBahn software solution for more advanced information. Then, if you are doing in depth repairs and do not need things "simplified" for you, (e.g. transmission rebuild, etc.); then, the eRwin is a good deal @ $35 for 24 hours access and you can download all the manual pages you need and save them, for later use.
I personally, have tried a bit of everything; a Haynes, a paper Bentley, Bentley eBahn software and the Erwin manuals. Each has its strengths and weaknesses; sometimes, having a paper manual is nice to have with you or you have to be looking at a computer to look at files or access things online. If you are using VCDS; you are using a windows based pc anyway, so it can be a effective combination. I think most pro techs; have gotten to the point, where online access and pc/web access based manuals, are the solution most are using now.
An example of this; would be All Data, another subscription service:
http://www.alldatadiy.com/index.html
Cars are to the pont; you need a pc or scan tool, to work on them and accessing repair info on a computer, is becoming necessary as well.