How do I download a version of swift?

I have ubuntu 10.11 installed on my system.

#1 likely means 11.10 Oneiric.
The version in bug report was released for precise, which in the meantime is 1.4.5.
1.4.4 0 doesn't seem to be backported to Oneiric main (yet), not sure if it will be.
Workaround is to enable ppa and then install via terminal.
https://launchpad.net/~swift-core/+archive/release

Of course the .deb file alone can be installed via dpkg -i, but might introduce dependency issues.

I've added

       deb http://ppa.launchpad.net/swift-core/release/ubuntu oneiric main
       deb-src http://ppa.launchpad.net/swift-core/release/ubuntu oneiric main

to the bottom of my /etc/apt/sources.list.

I've tried to install using:
      # apt-get install swift
      Reading package lists... Done
      Building dependency tree
      Reading state information... Done
      swift is already the newest version.
      0 upgraded, 0 newly installed, 0 to remove and 7 not upgraded.

and
      # apt-get install swift_1.4.4~20111108.1612-0ubuntu1
      Reading package lists... Done
      Building dependency tree
      Reading state information... Done
      E: Unable to locate package swift_1.4.4~20111108.1612-0ubuntu1
      E: Couldn't find any package by regex 'swift_1.4.4~20111108.1612-0ubuntu1'
      root@xyz01:/tmp# apt-get install swift
      Reading package lists... Done
      Building dependency tree
      Reading state information... Done
      swift is already the newest version.
      0 upgraded, 0 newly installed, 0 to remove and 7 not upgraded.

What am I still doing wrong?

Why did you add to sources.list, remove the 2 lines and do it the proper way.

sudo add-apt-repository ppa:swift-core/release; sudo apt-get update; sudo apt-get install swift

Thank you for providing the specific commands.
I've removed the 2 lines.
I'm currently getting the following error:

# sudo add-apt-repository ppa:swift-core/releaseTraceback (most recent call last):
  File "/usr/bin/add-apt-repository", line 88, in <module>
    ppa_info = get_ppa_info_from_lp(user, ppa_name)
  File "/usr/lib/python2.7/dist-packages/softwareproperties/ppa.py", line 65, in get_ppa_info_from_lp
    lp_page = urlopen(req).read()
  File "/usr/lib/python2.7/urllib2.py", line 126, in urlopen
    return _opener.open(url, data, timeout)
  File "/usr/lib/python2.7/urllib2.py", line 394, in open
    response = self._open(req, data)
  File "/usr/lib/python2.7/urllib2.py", line 412, in _open
    '_open', req)
  File "/usr/lib/python2.7/urllib2.py", line 372, in _call_chain
    result = func(*args)
  File "/usr/lib/python2.7/urllib2.py", line 1209, in https_open
    return self.do_open(httplib.HTTPSConnection, req)
  File "/usr/lib/python2.7/urllib2.py", line 1171, in do_open
    raise URLError(err)
urllib2.URLError: <urlopen error [Errno -3] Temporary failure in name resolution>

Can you give the output of:

lsb_release -a; uname -a

Thanks

# lsb_release -a; uname -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 11.10
Release: 11.10
Codename: oneiric
Linux dhachost01 3.0.0-12-server #20-Ubuntu SMP Fri Oct 7 16:36:30 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux

There is a reason why the note is on top page.
< Adding this PPA to your system
You can update your system with unsupported packages from this untrusted PPA by adding ppa:swift-core/release to your system's Software Sources. (*Read about installing*) >

Verify the lines are completely removed in sources.list and sources.list.d and to be sure disabled in software-sources third-party tab.
Reload package cache then try to add the ppa properly.

In case of remaining issues maybe try ppa-purge.
https://launchpad.net/ppa-purge

sudo apt-get install ppa-purge

After installation:
sudo ppa-purge ppa:swift-core/release

Please monitor if ppa-purge removes something else in case it needs to be reinstalled.

The lines are completely removed from sources.list and are not in sources.list.d.

I don't have the GUI. How do I disable in software-sources third-party via command line?
How do I reload the package cache via command line?

I get the same error ad in comment #5 when I try to apt-get install pap-purge.

What's the process steps for request that the fix for https://launchpad.net/swift/+bug/882679 be ported to Ubuntu 11.10?

If sources.list and sources.list.d are clear that's fine.
Updating package cache is only:
sudo apt-get update

Maybe try some repair tools which in case tell what to do next.
sudo dpkg --configure -a
sudo apt-get -f install

https://help.ubuntu.com/community/AptGet/Howto

>same error ... try to apt-get install pap-purge

It's ppa-purge.
Usage example.
http://www.webupd8.org/2009/12/remove-ppa-repositories-via-command.html

Reference for editing repos via cli.
https://help.ubuntu.com/community/Repositories/CommandLine

You could kindly request a backport to Oneiric in bug report.
Regarding the ppa issue maybe contact maintainer.