Anyone know of any decent microphones that utilize the RCA jacks on the XL1 or do I have to by the MA 100/Shoulder pad? I know professional mikes have XLR jacks but can I avoid this big cost?

I'm trying to get around this problem by making my own Balanced XLR connector to unbalance RCA connector. It just consists of an opamp with a split power supply. I'll tell you how it goes. I'm following one of the circuits you can find here.... http://www.tagmclarenaudio.com/members/news/news28.asp

keep me updated.

For about $20 you can buy an balanced to unbalanced matching transformer, about the size of a large cigar. They usually provide XLR to 1/4" phone or RCA conections. You can run a RCA cable from it to the XL1. Best place to find one is at a store that caters to musicians or professional audio. MARS Music is a nation wide chain that has them. So do many electronics parts outlets. Be sure to get one that does 600-to-600 ohms (or close to that ratio). Warning: The units I've seen at Radio Shack are mainly 600-to-50k ohm and may not give satisfactory results. Some brands I've seen have a switch and will do both 50k-to-600 and 600-to-600.

You can buy an adapter for about $7 that connects an XLR balanced to unbalanced, but then you loose much of the noise cancelling property of the XLR connection.

Note that the MA-100 gives an additonal 6 dB of gain, no gain is provided by the $20 adapters.

Yeah, I considered a transformer arrangement, but unfortunately you tend to get quality degredation. My op-amp arrangement shouldn't cost more than 20$ for the circuit, though on top of that is the XLR connectors and the like.
By just changing a few resistor values 6db will be easy enough to achieve.... we're talking about extrememly small signals here.

Paul. FWIW, that is what the guts of the MA-100 are, an electronic implementation executed with op amps, probably 4 per channel. At a street price well under $200, in a package designed to work with the XL1. Hard to justify a do-it-yourself approach if time has real value other than for the fun of building one.

Profesional quality matching transformers should give good results - more than adequate for all but the most critical music recording.

Well double the price and thats what you buy them for here in New Zealand, our curency isn't that strong against the US at the moment, so a device that costs 20$us to make compaired to 180$us I think is pretty good savings, especially when the support you get with the MA100 isn't very good to begin with, might as well make a sholder support as well.
Theres no reason they'd have 4 op-amps per channel, you'd just use 2 TL072's which are low noise dual amps, and theres your 4 channels. They cost around $1.00 each.
If you can make something of satisfactory quality yourself, that costs a lot less and does exactly the same job, I think you're a bit nutty not to give it a go.
But having said that, I agree that there are soem things that are better just bought, for instance a wireless mic setup :). To make a proper diversity UHF setup would cost more than buying a nice professionally made one methinks.

Actually there is reason to use multipel op amps per channel but that goes into circuit design.
Again, if one's time is worth money - better to buy. For talkingpurposes, assume takes on the order of 8 hours to build a decent substitute for the MA-100, counting design, hunting down parts, making the circuit board, assembling it in a decent looking package, testing, mountng it somewhere, and so on. If time is worth US$20 per hour, and US$20 for the parts (that sounds cheap), we are at the price of an MA-100. But as a recreational/hobby exercise or to occupy otherwise available time it is a money saver.