If the approach requires a DME arc or DME distance fixes and does not have an approved GPS or GPS/ARNAV (advanced area navigation, to be required at the upper FL's in 2005), you're stuck.  The FAA has started creating GPS based equivalent approaches to substitute for all approaches in (supposedly) the following priority:

1. NDB
2. VOR
3. VOR/DME
4. ILS (this will require WAAS and may still only be good for Cat 1)

IOW, if you typically fly where they clear you to a DME approach and they don't list a GPS equivalent, you need a DME.

If you have the panel space, a used KNS-80 can be had for ~$1000.  Yes, the RNAV is pretty useless by today's standards, but that's a cheap price for a DME/VOR/LOC/GS.

Eric Ahlstrom