There are really 2 questions you need to address first:
- Is the AS/400 on your local Lan in California?
- Will the warehouse in Texas also connect to other servers in California (email servers for instance) via WAN or other dedicated connection?
If the answer to both these questions is yes, then all you need to do is install Client Access on the remote PC. In the simplest environment, that would allow you to do both terminal access and printing to a locally attached printer on the same PC.
There are a lot more options for printing, including remote outq’s and sending the data to your file and print server print queues, but those do require some additional configuration.
If #1 above is not true, then you are very limited in your connection choices, and while connecting a modem an T1 will work, it might be a lot less expensive in the long run to do a system upgrade to allow TCP/IP connections to your AS/400, then connect thru your lan/wan. Especially now given the new pricing on the late model Power systems.
If # 2 above is not true and the warehouse in Texas isn’t connecting to servers in California, then you should really try to find a network consulting company (not affiliated with a service provider) to review your network and suggest options. There are myriad different service offerings from a wide variety of carriers such not just limited to the traditional phone companies and sorting them all out is not a simple task. The upfront costs associated with the consulting gig will probably easily be recovered in the savings they might find you on the connection costs.
A T1 is typically terminated at a router with an integrated CSU/DSU. You can have a point-to-point link for this purpose but it may be expensive. If the printer in Texas is a twinax printer then you will need a controller on that end. However, if it is TCP/IP then you can put the point-to-point link in place to service printing needs in Texas. You could implement a VPN connection between the two facilities but you would be best assisted in this effort by a local value added reseller where you are located. They will help you discover what gear and services are needed.
Learn about branch office networking. Here’s some resources to get started:
Cloud access or VPN. Then RDP. If you have the ability, those seem like the simplest answers to your question.
Hope this helps!