Hi,
Your project caught my eye because I just finished a similar project. By the way, thanks for the chuckle I got from your comment:
".... (worried about sensitivity) i really do not trust digital...".
You may want to work on this trust issue. This project is EVERYTHING digital! :o
Just kidding.
Our projects are somewhat similar. To see if what I did is something similar to your needs, I will briefly describe it.
I have an old friend who raises chickens for fast-food restaurants. He has 10 houses of about 5000 chickens each. He wanted to collect data as to all the environmental elements (temp, volatile gases, humidity, etc.) so he could better control electrical power usage on his ventilation system. Imagine how hot and stuffy it would get without proper ventilation. On the other hand, running the "wind tunnel" unnecessarily amounts to wasting power -- BIG TIME. He wanted an EXCEL log of all the environmental factors, collected throughout the day. So, I put together something that sounds similar to your project. Using a UNO, SD logger shield, and sensors, (64MB Sandisk SD card), the "sensor box" activates a small internal fan to bring in an air sample once every 10 minutes and then save all the sensor data to the SD card, capacity 64 MB. (This will accommodate about 45 days of samples taken every 10 minutes, in my case.) The "box" creates a fresh new data file every day at midnight. So, each file has 24 hours of environmental data that EXCEL will display, graph, etc. for my friend to analyze. The box has been installed for almost 30 days. (It has a front panel readout and activity LED to confirm that it's doing what it's designed.) We will remove the box and harvest the data in a week or so.
Does this sound like a parallel scenario for your project? If so, here's my suggestion (finally) based upon how I got mine working:
BASICS: (I apologize if this is over-simplified.)
1> First, get the SD card to function. That is, write a simple sketch without any other purpose but to write data to your card in the CSV (or other) format you want to have later when you retrieve the DATA.txt files from the SD card. Do a mock exercise and actually go through the steps of retrieving this data from the SD card, into EXCEL, and to be sure it's exactly what you want. There's nothing worse than to have days of data saved but in some goofy format that's unuseable. Precisely, what SD shield or device are you using?? You mentioned that parts are hard to get but hopefully you are using something pretty common and one with examples on the web from which you will get help. If it turns out that your and mine are the same, I will gladly share a snippet that I use if your hardware is identical. So, what SD setup are you using? If you're using a generic SD reader, you're on your own. I developed mine around an Adafruit SD shield that has a real-time clock and battery backup. I hope you have one or something very similar.
2> I have used the temp sensor you selected. It's just fine for most of my purposes. It's quite sensitive and outputs the temperature to an accuracy of 1 or 2 decimal places -- much higher resolution that I've every needed. I also have snippets of code for it if you don't. Let me know.
3> Decide the sampling rate and choose the SD card capacity for the duration. Exceeding the SD card capacity may be a problem - I don't know since I've never had an experience exceeding it. I don't know how the SD library handles that. It may over-write existing files or may just do nothing. Can't say for sure. So, I just use a SD card large enough for the task+. Re-reading your post, I see that you plan to sample only once per day. Why? I mean, data samples are free! Why not sample much more often to see "trends" or, perhaps help with the of digital data trust issue? 
Multiple samples that are stable serves to reassure that the data is, well, stable anyway.
Keep us posted. I need more information about your set up before recommending anything further.
Good luck,
GOV