The only 64-bit repository I know of is the active state one (Note: the x64 in the url): 

ppm> repo describe 1
Id: 1
Name: ActiveState Package Repository
URL: http://ppm4.activestate.com/MSWin32-x64/5.10/1004/package.xml
Enabled: yes
Last-Status: 200 OK
Last-Access: 1 week and 2 days ago
Refresh-In: overdue
Last-Modified: 1 week and 3 days ago

[download]

It currently lists a fairly small selection of CPAN which does not yet appear to include the Tk base package: 

ppm> search tk
Downloading ActiveState Package Repository packlist...done
Updating ActiveState Package Repository database...done
 1: Apache-AuthTkt 2.1
 2: Catalyst-Authentication-AuthTkt 0.10
 3: Catalyst-Plugin-Authentication-AuthTkt 0.02
 4: PDF-Tk 0.02
 5: Tie-Hash-StructKeyed 0.04
 6: Tie-ListKeyedHash 1.02
 7: Tk-Browser 0.82b
 8: Tk-DirSelect 1.03
 9: Tk-FileDialog 1.3
10: Tk-Getopt 0.50
11: Tk-Image-Calculation 0.04
12: Tk-LineGraphDataset 0.01
13: Tk-ObjectHandler 0.03
14: Tk-SelFile 0.02
15: Tk-SignalSlot 0.1
16: Tk-WaitBox 1.3
17: Tk-Workspace 1.75
18: VBTK 0.20
19: clickTk 4.013
20: oEdtk 0.41776w
21: ptkFAQ 0_03
22: ptkftp 1.00
23: vptk_w_2 38b

[download]

I suspect that it, in common with quite a few other modules with XS components and/or C library dependancies, will require considerable work by knowledgable people to make it 64-bit compatible.

You should note that it is perfectly fine to install and use the 32-bit AS distributions under XP-64.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

In reply to Re: Problems with Configuring PPM and Module Installations on Win XP-64 after Win XP by BrowserUk
in thread Problems with Configuring PPM and Module Installations on Win XP-64 after Win XP by ozboomer

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