Los Angeles
I don't think it has anything to do with the holidays, most of us has been back in town for at least a week, but more likely 2 weeks now... Everything is back to normal and things are busy as they've ever been for most ladies. It's not whether "money talks", it's whether your money talks to that particular lady, aka whether your planning styles are a match. If you contact someone whose schedule is flexible, who has a static incall and who is open to last minute appointments with the screening information you provide, it should be no problem.
Of course anyone who screens will not be ready on a moment's notice, at the very least she would have to run your information against the blacklists and most of us would like to talk to a few of your references too... But if you have the right screening info I would imagine same day appointments shouldn't be a problem. Many of the ladies I've talked to are able to accommodate you on a short notice. Those of us who have a life outside of this usually cannot see you the same day, because some have jobs, some have children, some live father out of LA, and most have made plans in advance, so we are probably not a good match for you.
If you need to see someone on a short notice, your best bet is probably an agency that keeps girls around, or visiting ladies who come here just to work. Also, ladies who have hours of availability on their website might be worth contacting, as well as those who post replies to ISO's, as they seem to be more available full-time. Anyone who is online in the chat room is also probably open to meeting on a shorter notice, or at least screening you on the spot and setting up something for the same day or the next, just like someone who is marked as "available now" on Eros or that "other unmentionable site".
I personally stay pretty busy with "real life", so I try to designate at least 2 days a week for screening, answering emails, scheduling, making travel arrangements, etc. For example, today is my "Nora day", I'm catching up on reading PM's, posts and the like. If you had contacted me 3 days ago, I would just be getting to it now... But I make it clear in my ads, on my website and in my email autoresponder that I need at least 48 hours to respond and screen, unless someone is an established friend, in which case he is welcome to send me a text message on my private number any time. Since my focus is on longer dates and in most cases I spend at least 12 hours with the gentleman I meet, I plan the majority of my calendar in advance, as to not interfere with my real work, leaving occasional time for established friends who might contact me on a shorter notice. Usually 90% of my schedule is worked out 2-3 weeks in advance, and that helps me stay on track. Most months I have very little time to meet new friends, so any last minute requests tend to go unanswered for a while, until I have time to sit down and get back to them. Guys who were looking for that "quick relief" would have long moved on by then, which is perfectly fine by me... 
I've talked to a number of local ladies and they seem to feel the same way. So again, if planning in advance is not an option or not what you like, agencies and visitors may be your best bet.