The key insight offered in this article is simply that B2B sites (and other web sites!) can lose customers if the ballpark price is not known early enough in the process, when your potential customer is evaluating vendors.
There are alternatives to offering details about your prices. You can try to offer ballpark estimates, as suggested. You might also try the approach that we use here at theSiteDoctor.com, which is to try to bring you - the customer - closer to us before we start talking about price.
In our case, we were able to bring you in closer by offering you something for free - a sample site report. This offer had the additional benefit (for us!) of qualifying you as a potential customer; you can only get a look at our pricing structure if you show us your site first.
The lesson here is that you should look for ways to get your customer to come closer if you are not going to offer price information on your site. And, to get your potential customer to come closer, you will probably need to identify something that he or she wants, and provide it for free.