Yes, you can convert a jpg to a pdf using the Adobe CreatePDF service. Here is a list of file formats that the Adobe CreatePDF supports:
To find out more details about the Adobe CreatePDF online service, please refer to this link:
To see the pricing options for the Adobe CreatePDF online service, please refer to this link:
File | Action Wizard | Create Action
select JPEG type
Well I guess Iserghio gave you a good answer already. CreatePDF is definitley the most professional choice!
If you are looking for a service to upload files larger than 100MB you should also have a look at http://jpg.smallpdf.com.